diff --git a/CHANGELOG.md b/CHANGELOG.md
index e797664c1..f50bcef57 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -35,6 +35,19 @@ mongodb:
 8. master ブランチに戻す
 9. enjoy
 
+11.4.0 (2019/04/25)
+-------------------
+### Improvements
+* 検索でローカルの投稿のみに絞れるように
+* 検索で特定のインスタンスの投稿のみに絞れるように
+* 検索で特定のユーザーの投稿のみに絞れるように
+
+### Fixes
+* 投稿が増殖する問題を修正
+* ストリームで過去の投稿が流れてくる問題を修正
+* モバイル版のユーザーページで遷移してもユーザー名が変わらない問題を修正
+* お知らせを切り替えても内容が変わらない問題を修正
+
 11.3.1 (2019/04/24)
 -------------------
 ### Fixes
diff --git a/package.json b/package.json
index 00cbdc73c..56a5ac0dc 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
 		"format": "gulp format"
 	},
 	"dependencies": {
+		"@elastic/elasticsearch": "7.0.0-rc.2",
 		"@fortawesome/fontawesome-svg-core": "1.2.15",
 		"@fortawesome/free-brands-svg-icons": "5.7.2",
 		"@fortawesome/free-regular-svg-icons": "5.7.2",
@@ -35,7 +36,6 @@
 		"@types/dateformat": "3.0.0",
 		"@types/deep-equal": "1.0.1",
 		"@types/double-ended-queue": "2.1.0",
-		"@types/elasticsearch": "5.0.32",
 		"@types/file-type": "10.9.1",
 		"@types/gulp": "4.0.6",
 		"@types/gulp-mocha": "0.0.32",
@@ -113,7 +113,6 @@
 		"deep-equal": "1.0.1",
 		"diskusage": "1.1.0",
 		"double-ended-queue": "2.1.0-0",
-		"elasticsearch": "15.4.1",
 		"emojilib": "2.4.0",
 		"eslint": "5.16.0",
 		"eslint-plugin-vue": "5.2.2",
diff --git a/src/client/app/common/scripts/gen-search-query.ts b/src/client/app/common/scripts/gen-search-query.ts
new file mode 100644
index 000000000..fc26cb7f7
--- /dev/null
+++ b/src/client/app/common/scripts/gen-search-query.ts
@@ -0,0 +1,31 @@
+import parseAcct from '../../../../misc/acct/parse';
+import { host as localHost } from '../../config';
+
+export async function genSearchQuery(v: any, q: string) {
+	let host: string;
+	let userId: string;
+	if (q.split(' ').some(x => x.startsWith('@'))) {
+		for (const at of q.split(' ').filter(x => x.startsWith('@')).map(x => x.substr(1))) {
+			if (at.includes('.')) {
+				if (at === localHost || at === '.') {
+					host = null;
+				} else {
+					host = at;
+				}
+			} else {
+				const user = await v.$root.api('users/show', parseAcct(at)).catch(x => null);
+				if (user) {
+					userId = user.id;
+				} else {
+					// todo: show error
+				}
+			}
+		}
+
+	}
+	return {
+		query: q.split(' ').filter(x => !x.startsWith('/') && !x.startsWith('@')).join(' '),
+		host: host,
+		userId: userId
+	};
+}
diff --git a/src/client/app/common/scripts/search.ts b/src/client/app/common/scripts/search.ts
index c44581817..2897ed631 100644
--- a/src/client/app/common/scripts/search.ts
+++ b/src/client/app/common/scripts/search.ts
@@ -3,7 +3,7 @@ import { faHistory } from '@fortawesome/free-solid-svg-icons';
 export async function search(v: any, q: string) {
 	q = q.trim();
 
-	if (q.startsWith('@')) {
+	if (q.startsWith('@') && !q.includes(' ')) {
 		v.$router.push(`/${q}`);
 		return;
 	}
diff --git a/src/client/app/common/views/components/user-list.vue b/src/client/app/common/views/components/user-list.vue
index b8bcc35d8..53577bad0 100644
--- a/src/client/app/common/views/components/user-list.vue
+++ b/src/client/app/common/views/components/user-list.vue
@@ -60,9 +60,9 @@ export default Vue.extend({
 	},
 
 	methods: {
-		init() {
+		async init() {
 			this.fetching = true;
-			this.makePromise().then(x => {
+			await (this.makePromise()).then(x => {
 				if (Array.isArray(x)) {
 					this.us = x;
 				} else {
@@ -76,9 +76,9 @@ export default Vue.extend({
 			});
 		},
 
-		fetchMoreUsers() {
+		async fetchMoreUsers() {
 			this.fetchingMoreUsers = true;
-			this.makePromise(this.cursor).then(x => {
+			await (this.makePromise(this.cursor)).then(x => {
 				this.us = this.us.concat(x.users);
 				this.cursor = x.cursor;
 				this.fetchingMoreUsers = false;
diff --git a/src/client/app/common/views/deck/deck.notes.vue b/src/client/app/common/views/deck/deck.notes.vue
index bc67f4911..680b44bc8 100644
--- a/src/client/app/common/views/deck/deck.notes.vue
+++ b/src/client/app/common/views/deck/deck.notes.vue
@@ -110,11 +110,11 @@ export default Vue.extend({
 			this.init();
 		},
 
-		init() {
+		async init() {
 			this.queue = [];
 			this.notes = [];
 			this.fetching = true;
-			this.makePromise().then(x => {
+			await (this.makePromise()).then(x => {
 				if (Array.isArray(x)) {
 					this.notes = x;
 				} else {
@@ -129,10 +129,10 @@ export default Vue.extend({
 			});
 		},
 
-		fetchMore() {
+		async fetchMore() {
 			if (!this.more || this.moreFetching) return;
 			this.moreFetching = true;
-			this.makePromise(this.notes[this.notes.length - 1].id).then(x => {
+			await (this.makePromise(this.notes[this.notes.length - 1].id)).then(x => {
 				this.notes = this.notes.concat(x.notes);
 				this.more = x.more;
 				this.moreFetching = false;
diff --git a/src/client/app/common/views/deck/deck.search-column.vue b/src/client/app/common/views/deck/deck.search-column.vue
index ab19bdaab..17ee2ef45 100644
--- a/src/client/app/common/views/deck/deck.search-column.vue
+++ b/src/client/app/common/views/deck/deck.search-column.vue
@@ -14,6 +14,7 @@
 import Vue from 'vue';
 import XColumn from './deck.column.vue';
 import XNotes from './deck.notes.vue';
+import { genSearchQuery } from '../../../common/scripts/gen-search-query';
 
 const limit = 20;
 
@@ -25,10 +26,10 @@ export default Vue.extend({
 
 	data() {
 		return {
-			makePromise: cursor => this.$root.api('notes/search', {
+			makePromise: async cursor => this.$root.api('notes/search', {
 				limit: limit + 1,
 				offset: cursor ? cursor : undefined,
-				query: this.q
+				...(await genSearchQuery(this, this.q))
 			}).then(notes => {
 				if (notes.length == limit + 1) {
 					notes.pop();
diff --git a/src/client/app/desktop/views/components/notes.vue b/src/client/app/desktop/views/components/notes.vue
index 9044ad347..87fdc749d 100644
--- a/src/client/app/desktop/views/components/notes.vue
+++ b/src/client/app/desktop/views/components/notes.vue
@@ -105,9 +105,9 @@ export default Vue.extend({
 			this.init();
 		},
 
-		init() {
+		async init() {
 			this.fetching = true;
-			this.makePromise().then(x => {
+			await (this.makePromise()).then(x => {
 				if (Array.isArray(x)) {
 					this.notes = x;
 				} else {
@@ -122,7 +122,7 @@ export default Vue.extend({
 			});
 		},
 
-		fetchMore() {
+		async fetchMore() {
 			if (!this.more || this.moreFetching || this.notes.length === 0) return;
 			this.moreFetching = true;
 			this.makePromise(this.notes[this.notes.length - 1].id).then(x => {
diff --git a/src/client/app/desktop/views/home/search.vue b/src/client/app/desktop/views/home/search.vue
index 84153d18c..50c645615 100644
--- a/src/client/app/desktop/views/home/search.vue
+++ b/src/client/app/desktop/views/home/search.vue
@@ -14,6 +14,7 @@
 import Vue from 'vue';
 import i18n from '../../../i18n';
 import Progress from '../../../common/scripts/loading';
+import { genSearchQuery } from '../../../common/scripts/gen-search-query';
 
 const limit = 20;
 
@@ -21,10 +22,10 @@ export default Vue.extend({
 	i18n: i18n('desktop/views/pages/search.vue'),
 	data() {
 		return {
-			makePromise: cursor => this.$root.api('notes/search', {
+			makePromise: async cursor => this.$root.api('notes/search', {
 				limit: limit + 1,
 				offset: cursor ? cursor : undefined,
-				query: this.q
+				...(await genSearchQuery(this, this.q))
 			}).then(notes => {
 				if (notes.length == limit + 1) {
 					notes.pop();
diff --git a/src/client/app/mobile/views/components/notes.vue b/src/client/app/mobile/views/components/notes.vue
index 2e4230071..5ad80c286 100644
--- a/src/client/app/mobile/views/components/notes.vue
+++ b/src/client/app/mobile/views/components/notes.vue
@@ -106,9 +106,9 @@ export default Vue.extend({
 			this.init();
 		},
 
-		init() {
+		async init() {
 			this.fetching = true;
-			this.makePromise().then(x => {
+			await (this.makePromise()).then(x => {
 				if (Array.isArray(x)) {
 					this.notes = x;
 				} else {
@@ -123,10 +123,10 @@ export default Vue.extend({
 			});
 		},
 
-		fetchMore() {
+		async fetchMore() {
 			if (!this.more || this.moreFetching || this.notes.length === 0) return;
 			this.moreFetching = true;
-			this.makePromise(this.notes[this.notes.length - 1].id).then(x => {
+			await (this.makePromise(this.notes[this.notes.length - 1].id)).then(x => {
 				this.notes = this.notes.concat(x.notes);
 				this.more = x.more;
 				this.moreFetching = false;
diff --git a/src/client/app/mobile/views/pages/search.vue b/src/client/app/mobile/views/pages/search.vue
index 0225dd9e9..45f383790 100644
--- a/src/client/app/mobile/views/pages/search.vue
+++ b/src/client/app/mobile/views/pages/search.vue
@@ -12,6 +12,7 @@
 import Vue from 'vue';
 import i18n from '../../../i18n';
 import Progress from '../../../common/scripts/loading';
+import { genSearchQuery } from '../../../common/scripts/gen-search-query';
 
 const limit = 20;
 
@@ -19,10 +20,10 @@ export default Vue.extend({
 	i18n: i18n('mobile/views/pages/search.vue'),
 	data() {
 		return {
-			makePromise: cursor => this.$root.api('notes/search', {
+			makePromise: async cursor => this.$root.api('notes/search', {
 				limit: limit + 1,
 				untilId: cursor ? cursor : undefined,
-				query: this.q
+				...(await genSearchQuery(this, this.q))
 			}).then(notes => {
 				if (notes.length == limit + 1) {
 					notes.pop();
diff --git a/src/db/elasticsearch.ts b/src/db/elasticsearch.ts
index d54b01763..02c9e88d9 100644
--- a/src/db/elasticsearch.ts
+++ b/src/db/elasticsearch.ts
@@ -1,41 +1,30 @@
-import * as elasticsearch from 'elasticsearch';
+import * as elasticsearch from '@elastic/elasticsearch';
 import config from '../config';
-import Logger from '../services/logger';
-
-const esLogger = new Logger('es');
 
 const index = {
 	settings: {
 		analysis: {
-			normalizer: {
-				lowercase_normalizer: {
-					type: 'custom',
-					filter: ['lowercase']
-				}
-			},
 			analyzer: {
-				bigram: {
-					tokenizer: 'bigram_tokenizer'
-				}
-			},
-			tokenizer: {
-				bigram_tokenizer: {
-					type: 'nGram',
-					min_gram: 2,
-					max_gram: 2
+				ngram: {
+					tokenizer: 'ngram'
 				}
 			}
 		}
 	},
 	mappings: {
-		note: {
-			properties: {
-				text: {
-					type: 'text',
-					index: true,
-					analyzer: 'bigram',
-					normalizer: 'lowercase_normalizer'
-				}
+		properties: {
+			text: {
+				type: 'text',
+				index: true,
+				analyzer: 'ngram',
+			},
+			userId: {
+				type: 'keyword',
+				index: true,
+			},
+			userHost: {
+				type: 'keyword',
+				index: true,
 			}
 		}
 	}
@@ -43,31 +32,20 @@ const index = {
 
 // Init ElasticSearch connection
 const client = config.elasticsearch ? new elasticsearch.Client({
-	host: `${config.elasticsearch.host}:${config.elasticsearch.port}`
+	node: `http://${config.elasticsearch.host}:${config.elasticsearch.port}`,
+	pingTimeout: 30000
 }) : null;
 
 if (client) {
-	// Send a HEAD request
-	client.ping({
-		// Ping usually has a 3000ms timeout
-		requestTimeout: 30000
-	}, error => {
-		if (error) {
-			esLogger.error('elasticsearch is down!');
-		} else {
-			esLogger.succ('elasticsearch is available!');
-		}
-	});
-
 	client.indices.exists({
-		index: 'misskey'
+		index: 'misskey_note'
 	}).then(exist => {
-		if (exist) return;
-
-		client.indices.create({
-			index: 'misskey',
-			body: index
-		});
+		if (!exist.body) {
+			client.indices.create({
+				index: 'misskey_note',
+				body: index
+			});
+		}
 	});
 }
 
diff --git a/src/server/api/endpoints/notes/search.ts b/src/server/api/endpoints/notes/search.ts
index daf992b63..65ce20074 100644
--- a/src/server/api/endpoints/notes/search.ts
+++ b/src/server/api/endpoints/notes/search.ts
@@ -5,6 +5,7 @@ import { ApiError } from '../../error';
 import { Notes } from '../../../../models';
 import { In } from 'typeorm';
 import { types, bool } from '../../../../misc/schema';
+import { ID } from '../../../../misc/cafy-id';
 
 export const meta = {
 	desc: {
@@ -29,7 +30,17 @@ export const meta = {
 		offset: {
 			validator: $.optional.num.min(0),
 			default: 0
-		}
+		},
+
+		host: {
+			validator: $.optional.nullable.str,
+			default: undefined
+		},
+
+		userId: {
+			validator: $.optional.nullable.type(ID),
+			default: null
+		},
 	},
 
 	res: {
@@ -54,30 +65,51 @@ export const meta = {
 export default define(meta, async (ps, me) => {
 	if (es == null) throw new ApiError(meta.errors.searchingNotAvailable);
 
-	const response = await es.search({
-		index: 'misskey',
-		type: 'note',
+	const userQuery = ps.userId != null ? [{
+		term: {
+			userId: ps.userId
+		}
+	}] : [];
+
+	const hostQuery = ps.userId == null ?
+		ps.host === null ? [{
+			bool: {
+				must_not: {
+					exists: {
+						field: 'userHost'
+					}
+				}
+			}
+		}] : ps.host !== undefined ? [{
+			term: {
+				userHost: ps.host
+			}
+		}] : []
+	: [];
+
+	const result = await es.search({
+		index: 'misskey_note',
 		body: {
 			size: ps.limit!,
 			from: ps.offset,
 			query: {
-				simple_query_string: {
-					fields: ['text'],
-					query: ps.query,
-					default_operator: 'and'
+				bool: {
+					must: [{
+						simple_query_string: {
+							fields: ['text'],
+							query: ps.query.toLowerCase(),
+							default_operator: 'and'
+						},
+					}, ...hostQuery, ...userQuery]
 				}
 			},
-			sort: [
-				{ _doc: 'desc' }
-			]
+			sort: [{
+				_doc: 'desc'
+			}]
 		}
 	});
 
-	if (response.hits.total === 0) {
-		return [];
-	}
-
-	const hits = response.hits.hits.map((hit: any) => hit.id);
+	const hits = result.body.hits.hits.map((hit: any) => hit._id);
 
 	if (hits.length === 0) return [];
 
diff --git a/src/services/note/create.ts b/src/services/note/create.ts
index 53e77b4ef..dd47632ca 100644
--- a/src/services/note/create.ts
+++ b/src/services/note/create.ts
@@ -435,11 +435,12 @@ function index(note: Note) {
 	if (note.text == null || config.elasticsearch == null) return;
 
 	es!.index({
-		index: 'misskey',
-		type: 'note',
+		index: 'misskey_note',
 		id: note.id.toString(),
 		body: {
-			text: note.text
+			text: note.text.toLowerCase(),
+			userId: note.userId,
+			userHost: note.userHost
 		}
 	});
 }