I did a search for "Jackass"... I got 450+ results, and no two items on the list have the same size. Then I did a search for "spears" and got 1300+ results, still with no two items on the list with the same size.

If you really are getting the results you say you are, please sort by size and take a screen shot so I can see. The only thing I could think of that might make two files appear with the same file size is is sometimes takes a few seconds for new search results to be sorted into the list.