This is really cool. I would, however, want to see an option where I could select a paper that falls into multiple categories. For instance, I was searching for a paper that may cover applications of NLP in history reconstruction, but I couldn't find any if I put as the keyword, let's say "history." This search term is very vague and it may apply to any result. It would be cool if one could access the results in multiple fields while searching for a vague/general theme.