I suggested in earis's journal yesterday that books that support GLBT rights don't usually use forms of "homosexual" in their titles. They use "gay" or "lesbian" or "bisexual" or "transgender" or "queer" or "GLBT" (with initials in some order). It's possible that the results you're getting are the same results you would have gotten before the tampering.

Then again, I just tried testing this claim by searching for "homosexuality" at Powells Books and comparing that search with the same one at Amazon. The results at Powells are significantly more positive than those at Amazon.