Is there an issue with Contents>contain? Trying to find a word in a PDF using contain gives me no results. Using "contain match" finds the word without a problem. I'm on Hazel 3.1.5.
"Contents contains" uses Spotlight so if there's an issue with Spotlight indexing that file, it will affect Hazel as well. You can test this by searching for the term in Spotlight. If the file in question doesn't show up, it won't match in Hazel either.