Searching for keywords in title with "all metadata" gives no results

I have an ongoing problem searching for particular files in Bridge. I've gone through and added keywords to my graphics files, as well as a lot of files have keywords in the names. For example, I have a png file "bluerose1.png." As keywords I put "watercolor" "flower," "floral," but not rose,  or blue, because that's already in the title. But when I do a search in the whole folder, and choose "all metadata" with the keywords watercolor and rose, "all criteria are met," it won't find the rose, and in fact I'll get a "No results" message. Even though I know for a fact that particular file is in that folder. If I choose "If any criteria are met," I'll get ALL the files tagged with watercolor, even though they aren't roses. So why doesn't Bridge find the keywords that are in the titles, as well as in the keywords? Windows finds the keywords in the titles just fine, but it doens't pick up the keywords that I've added with Bridge for png files, only for jpegs.