Max, there was too much information to be found. You apparently used the default "Match all words" parameter which made your search fail. Just "maps" with the rest of your choices gave five answers, all of which were relevant.
Although mostly more is more and less is less, in this case less is more. The maps can be called "field" maps, "tactical" maps, "clipboard" maps and whatnot without being dedicated to AH3. Thus the time frame, one single word and the name of the author was all that was needed.
And yes, Google does it much better than SMF but they also have a much larger database and a much, much more powerful search engine to fumble through it.