Multiple people reported that they are unable to see online games which are hosted by their steam friends. This is most likely a problem locally, however I added a button ( which design still in progress ) to open a menu with all your stream friends. You will able to see all your friend, however you can send invite to the ones who has the game. I displayed the offline friends also to ensure nobody will be confused and think it is broken. The friend can accept the invite via the chat window, which should just join your session and you can start to play.
I hope it helps, however since the search problem mostly caused by a firewall block or antivirus software It might not fix the problem for everybody, but will make the hosting easier.
In the future there will be a refresh button also, however steam refuse to refresh the friend list automatically, a plugin needs to be written which will cause a bit delay. Expect the fully functioning system within 3 days.