I also tried the search ads. At first I too listed all of my items. But then I started narrowing it down because I noticed that there were a lot of times when an item would be displayed in a search whose search terms weren't really a very good match. So, there is definitely some tweaking you can do to make it better for you. But, even after all of the tweaking I did, I quite doing it and have noticed that the views and favorites to my store didn't really change. So, I think just being in the forums, selecting favorites, creating treasuries, adding sellers to my circle and just being active here are much more effective.