Add search features of MongoDB Atlas (#321)

Author: bilgeyucel

integrations/mongodb.md

@@ -25,9 +25,9 @@ version: Haystack 2.0
 
 ## Overview
 
-[MongoDB](https://www.mongodb.com/) is a document database designed for ease of application development and scaling. [MongoDB Atlas](https://www.mongodb.com/atlas) is a multi-cloud database service built by people behind MongoDB. MongoDB Atlas simplifies deploying and managing your databases while offering the versatility you need to build resilient and performant global applications on the cloud providers of your choice.
+[MongoDB](https://www.mongodb.com/) is a document database designed to ease application development and scaling. [MongoDB Atlas](https://www.mongodb.com/atlas) is a multi-cloud database service built by the people behind MongoDB. MongoDB Atlas simplifies deploying and managing your databases while offering the versatility you need to build resilient and performant global applications on the cloud providers of your choice.
 
-For a detailed overview of all the available methods and settings for the `MongoDBAtlasDocumentStore`, visit the Haystack [Documentation](https://docs.haystack.deepset.ai/docs/mongodbatlasdocumentstore).
+You can use MongoDB Atlas's **full-text** and **semantic search** features through [MongoDBAtlasFullTextRetriever](https://docs.haystack.deepset.ai/docs/mongodbatlasfulltextretriever) and [MongoDBAtlasEmbeddingRetriever](https://docs.haystack.deepset.ai/docs/mongodbatlasembeddingretriever). For a detailed overview of all settings for the `MongoDBAtlasDocumentStore`, visit the [Haystack Documentation](https://docs.haystack.deepset.ai/docs/mongodbatlasdocumentstore).
 
 ## Installation