My steam's friends list is not fonctionning properly. Help plz?

hello everyone

i'm having a problem with my friend list, i recently added a friend of mine on my list. I can chat with him and do voice conversation , but the only thing i cant do is see what he's playing.

For example when i go to servers and i click on the friends tab, it always says " None of your friends are currently playing this game " even when he is playing in a server ... Can you please help, I need to see in wish server he's playing so can join him.

Thank you, for anyone trying to help me