I did come across this site, but the results here are finite and few:
Is there are better way to search for this? Or anyway, a better search engine?
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Not free, but our individual download site has a waveform viewer: http://download.prosoundeffects.com There's also a "Sonic Search" function that looks for tracks sonically similar to a particular YouTube or Soundcloud track. It was originally designed for music, but it might give you some interesting results for sound effects too. Click the up arrow in the search bar to access that function.
Get one free download here: http://www.prosoundeffects.com/online-library-trial-1-download.html