empty network browser?

I'm new to the mac world, so I'm not sure how to fix this problem:

The "network" icon in the sidebar of my finder does not show anything when I click on it, even though I can connect to a computer on the network via "connect to server" (apple + k). How do I fix the emptiness of this browser? While it's no problem to use apple + k, I would like to know what computers are possible via GUI.

I've tried to search this subject numerous times, so either I'm not using the right keywords or the solution was never posted.

Thanks.

 

Sometimes it will show other macs that have shared a school network with me after I have come home from campus (I live about 15 miles away from campus).

I don't think it has ever shown me my computers on my home network.

 

Anyone have any ideas? I can't even see my own home folder on the network browser.