Get all documents where document field contains value

Question

I'm wondering if I can search through all documents and return all the documents that contain a specific word in a field.

Example

/games
      (docID1)
             genre: action
             name: battlefield V
      (docID2)
             genre: action
             name: battlefield 2
      (docID3)
             genre: action
             name: World of warcraft
      (docID4)
             genre: action
             name: Call of duty

I want to retrieve all the documents where the name = battlefield.. so with a contains. Now I've used the following:

this.db.collection('games', g => g.where('name', '==', SEARCHITEM))

This only gives one document back and it has to be a correct match (battlefield 2). I can't seem to find the solution for my problem.