diff --git a/app/containers/MessageBox/index.tsx b/app/containers/MessageBox/index.tsx
index 647c0e614ca..597fbadf8e9 100644
--- a/app/containers/MessageBox/index.tsx
+++ b/app/containers/MessageBox/index.tsx
@@ -51,7 +51,7 @@ import { IMessage } from '../../definitions/IMessage';
 import { forceJpgExtension } from './forceJpgExtension';
 import { IBaseScreen, IPreviewItem, IUser, TSubscriptionModel, TThreadModel } from '../../definitions';
 import { MasterDetailInsideStackParamList } from '../../stacks/MasterDetailStack/types';
-import { getPermalinkMessage, hasPermission, search, sendFileMessage } from '../../lib/methods';
+import { getPermalinkMessage, hasPermission, search, sendFileMessage, mentionsSearch } from '../../lib/methods';
 import { Services } from '../../lib/services';
 import { TSupportedThemes } from '../../theme';
 
@@ -571,7 +571,8 @@ class MessageBox extends Component<IMessageBoxProps, IMessageBoxState> {
 	};
 
 	getUsers = debounce(async (keyword: any) => {
-		let res = await search({ text: keyword, filterRooms: false, filterUsers: true });
+		const { rid, roomType } = this.props;
+		let res = await mentionsSearch({ text: keyword, rid, roomType, filterRooms: false, filterUsers: true });
 		res = [...this.getFixedMentions(keyword), ...res];
 		this.setState({ mentions: res, mentionLoading: false });
 	}, 300);
diff --git a/app/definitions/ISubscription.ts b/app/definitions/ISubscription.ts
index e2e6f2739a7..a0bee7bc2c9 100644
--- a/app/definitions/ISubscription.ts
+++ b/app/definitions/ISubscription.ts
@@ -18,6 +18,14 @@ export enum SubscriptionType {
 	E2E = 'e2e', // FIXME: this is not a type of subscription
 	THREAD = 'thread' // FIXME: this is not a type of subscription
 }
+export enum ReverseSubscriptionType {
+	'p' = SubscriptionType.GROUP,
+	'd' = SubscriptionType.DIRECT,
+	'c' = SubscriptionType.CHANNEL,
+	'l' = SubscriptionType.OMNICHANNEL,
+	'e2e' = SubscriptionType.E2E,
+	't' = SubscriptionType.THREAD
+}
 
 export interface IVisitor {
 	_id?: string;
diff --git a/app/lib/methods/search.ts b/app/lib/methods/search.ts
index d8f0f7d1a5b..739727d881c 100644
--- a/app/lib/methods/search.ts
+++ b/app/lib/methods/search.ts
@@ -2,13 +2,18 @@ import { Q } from '@nozbe/watermelondb';
 
 import { sanitizeLikeString } from '../database/utils';
 import database from '../database/index';
-import { spotlight } from '../services/restApi';
-import { ISearch, ISearchLocal, SubscriptionType } from '../../definitions';
+import { spotlight, getRoomMembers } from '../services/restApi';
+import { ISearch, ISearchLocal, SubscriptionType, ReverseSubscriptionType } from '../../definitions';
 import { isGroupChat } from './helpers';
 
 let debounce: null | ((reason: string) => void) = null;
 
-export const localSearch = async ({ text = '', filterUsers = true, filterRooms = true }): Promise<(ISearch | ISearchLocal)[]> => {
+export const localSearch = async ({
+	text = '',
+	filterUsers = true,
+	filterRooms = true,
+	spliceIndex = 7
+}): Promise<(ISearch | ISearchLocal)[]> => {
 	const searchText = text.trim();
 	const db = database.active;
 	const likeString = sanitizeLikeString(searchText);
@@ -19,15 +24,12 @@ export const localSearch = async ({ text = '', filterUsers = true, filterRooms =
 			Q.experimentalSortBy('room_updated_at', Q.desc)
 		)
 		.fetch();
-
 	if (filterUsers && !filterRooms) {
 		subscriptions = subscriptions.filter(item => item.t === 'd' && !isGroupChat(item));
 	} else if (!filterUsers && filterRooms) {
 		subscriptions = subscriptions.filter(item => item.t !== 'd' || isGroupChat(item));
 	}
-
-	const sliceSubscriptions = subscriptions.slice(0, 7);
-
+	const sliceSubscriptions = subscriptions.slice(0, spliceIndex === -1 ? subscriptions.length : spliceIndex);
 	const search = sliceSubscriptions.map(sub => ({
 		rid: sub.rid,
 		name: sub.name,
@@ -38,7 +40,6 @@ export const localSearch = async ({ text = '', filterUsers = true, filterRooms =
 		lastMessage: sub.lastMessage,
 		...(sub.teamId && { teamId: sub.teamId })
 	})) as (ISearch | ISearchLocal)[];
-
 	return search;
 };
 
@@ -96,3 +97,88 @@ export const search = async ({ text = '', filterUsers = true, filterRooms = true
 		return data;
 	}
 };
+
+export const mentionsSearch = async ({
+	text = '',
+	rid,
+	roomType,
+	filterUsers = true,
+	filterRooms = true
+}: {
+	text: string;
+	rid: string;
+	roomType: string;
+	filterUsers: boolean;
+	filterRooms: boolean;
+}): Promise<(ISearch | ISearchLocal)[]> => {
+	const searchText = text.trim();
+
+	if (debounce) {
+		debounce('cancel');
+	}
+
+	const localSearchData = await localSearch({ text, filterUsers, filterRooms, spliceIndex: -1 });
+	const usernames = localSearchData.map(sub => sub.name);
+
+	const data = localSearchData as (ISearch | ISearchLocal)[];
+	try {
+		if (localSearchData.length < 7) {
+			const { users, rooms } = (await Promise.race([
+				spotlight(searchText, usernames, { users: filterUsers, rooms: filterRooms }),
+				new Promise((resolve, reject) => (debounce = reject))
+			])) as { users: ISearch[]; rooms: ISearch[] };
+			if (filterUsers) {
+				users
+					.filter((item1, index) => users.findIndex(item2 => item2._id === item1._id) === index) // Remove duplicated data from response
+					.filter(user => !data.some(sub => user.username === sub.name)) // Make sure to remove users already on local database
+					.forEach(user => {
+						data.push({
+							...user,
+							rid: user.username,
+							name: user.username,
+							t: SubscriptionType.DIRECT,
+							search: true
+						});
+					});
+			}
+			if (filterRooms) {
+				rooms.forEach(room => {
+					// Check if it exists on local database
+					const index = data.findIndex(item => item.rid === room._id);
+					if (index === -1) {
+						data.push({
+							...room,
+							rid: room._id,
+							search: true
+						});
+					}
+				});
+			}
+		}
+		const roomTypeSub = (<any>ReverseSubscriptionType)[roomType];
+		const regex = new RegExp(`^${searchText}`);
+		const roomInfo = await getRoomMembers({
+			rid,
+			roomType: roomTypeSub,
+			type: 'all',
+			filter: false,
+			skip: 0,
+			allUsers: true,
+			limit: 7
+		});
+		let setData;
+		const roomUsers = roomInfo.map((x: any) => x.username);
+		let tempData = data.filter(user => user.name.match(regex));
+		tempData = tempData.filter(user => roomUsers.includes(user.name));
+		// TODO: add the conditions to check whether external mentions are allowed
+		setData = new Set([...tempData, ...data.filter(user => user.name.match(regex))]);
+		setData = new Set([...setData, ...data.filter(user => roomUsers.includes(user.name))]);
+		// TODO: add the conditions to check whether external mentions are allowed
+		setData = new Set([...setData, ...data]);
+		debounce = null;
+		return [...setData].splice(0, 7);
+	} catch (e) {
+		console.warn(e);
+		return data;
+	}
+};