The way I do it (and I'm not sure this is the best way because sometimes I get pages that just use a word from the set I'm searching on and not the whole set -- sorry, I'm probably confusing you) is to go to the scrapbooking gallery here:
12x12 by smadson at Splitcoaststampers
then I select 12 X 12 (what I use) and in the search function in the left bar, click search and I type in the set I want in quotes. For example "Wild About You" and this is the search results.
12x12 by smadson at Splitcoaststampers
Hope this helped.