I could be wrong but I've noticed this too. When you do a search it will show the number of results next to the search terms in the little tab above the file listing. It may say something like 213 but you have nowhere near that many listings.

Keep in mind that several of those listings are actually multiple files. The number just to the left of the file name tells how many of that particular file exists on the network. That's why you get such a high result number.

I've seen a couple files with as many as 120 copies available..