I'm not even sure I would find all of my own models if my only tool was that search dialog.
The present set of categories may have been meaningful in the first year or so, but anything that is not
obviously jewelry, art or puzzle tends to end up in miniatures.
Having to use quotes (without this being mentioned somewhere) is bad enough, but unless I have
overlooked something, one cannot use boolean operators, not even just AND, in search terms.
So if you are unlucky, you then have to wade through tens of pages of mostly unrelated stuff that
just happens to have one of the several search terms somewhere - more often than not in a
completely different context, cf. the recent thread about battlebot weapons turning up in a
search for bridal accessories.
Tags are almost useless as they appear to be essentially free text, everybody seems to be
invited to create new ones and nobody gets to see a list of them (except for the chosen few
tags that happen to be listed as being "popular" on the homepage) ? The search box does not
appear to understand them as a subcategory either, so to specifically search for a tag, one either
has to copy the search/tag?tag= URL line from the "search popular tags" on the homepage and
blindly try your own texts, or you hit on one shop item by some means and then try all of its "keywords"
in the hope that it returns a mostly relevant list. (Needless to say, there does not seem to be a means
of searching by keyword within the subset marked with a given tag...)
Just watching the "feed" from time to time and following up on interesting models may be more rewarding
than trying to search for something, but this is probably not what a "passerby" in search of n-scale hydrants
would do.
PS: the "paid ads" that TerryNathan suspected are probably just things that got pushed up in the results list by
"number of sales" or "number of views", but as this is not one of the user-selectable sort criteria it is probably
not a good idea as long as "relevance" to the search criteria is not always assured.