Newbie ranger needs some basic help understanding track

[Chinetter]

I think I am not understanding how the track skill works...my lvl4 ranger trained 10 points into it. I click on track and up pops the tracking window. It lists the nearby guards plus a couple of mobs, this is while standing in front of Kaladim.

But the list never changes. I click the "track" button over and over, no change. Even though various mobs are walking right by me, they never appear on the track window list. It's as if the list never refreshes...what am I missing here?