The search function here at Moviepilot.com is... erm, not so great. But fortunately you can use Google in the following way as a workaround:
where "_____ (fill in the blank)" is your search terms. For example, for discussion posts pertaining to "Kryptonite" you would enter
and Google will fetch the results, e.g.,
To refine the search results use the "+" sign. For example, to search for a post about kryptonite by a particular creator, for the search term type:
site:moviepilot.com, kryptonite+jay kelley
Or if you want to search specifically for a film and a subject:
site:moviepilot.com, batman v superman+kryptonite
This little trick may be known to a great many users, but I see no mention of it in the Moviepilot.com FAQ, so I just figured I would share. Cheers, and happy hunting for post subjects that are of greatest interest to you!