Hmm... the way I use it is that when I put the mouse on an item, that is the one I am looking at. So it is fine that some others are hidden. And when I want to see all items again, I move the mouse into an empty area (usually right next to the item I just looked at) so the popup goes away.
Also, I usually use the filters first. Say for laptops, I set the screen size to >=12inch and the weight to <=3pounds. So there ain't that many items left on the screen.
Do you use it differently?