You're actually asking about searching in your Art Library, not the same as the Marketplace search, although Art Library will turn-up some results from the Marketplace, as well as pulling from your personal Library and also From The Web. You'll get much more reduced results if you go to the Marketplace itself and try searching there, <a href="https://marketplace.roll20.net/" rel="nofollow">https://marketplace.roll20.net/</a> In the Art Library search, of course use the dropdown for Tokens or Maps or Portraits or Everything. It helps but not perfect, as you found. Also expand your terminology, if you found that "Rat" is not helpful, try searching for "rat rodent" or "giant rat" or "dirty rat" or "sewer rat", something like this should help narrow down the results. The word rat alone is quite common and as you found, it is sometimes an artist's name tag also which clouds the results. One more suggestion, go and find the actual picture in Google Images (in another browser tab). Once you find the picture of the rat you want, copy the file name. Return to Roll20 Art Search and put the word rat along with your google search term, and add the file name (such as Rat216411345.jpg). This will let you re-find in Roll20, the picture that you found you liked in Google. Art Library documentation: <a href="https://wiki.roll20.net/Art_Library" rel="nofollow">https://wiki.roll20.net/Art_Library</a>
