Multiplayer only for my game

how do i make it so that when the player refreshes the host list for the unity masterserver, it only shows him rooms that are using his version of his game.
right now it shows me my game, but also every other random unity project that uses the masterserver

The master server link you are connecting to is a testing one. You’ll host your own master server, and only your game will connect to it. See the Advanced documentation here:

http://docs.unity3d.com/Manual/net-MasterServer.html