I've given some light thought to this: There are several which are considered "good starting words", that mainly contain lots of vowels or most common used letters (such as "audio", Raise, etc). Then, as a second word, you could use another word that complements those letters (audio/rents, raise/mould ).

But there is a better strategy (similar to what is used in those interview puzzles of "From N weights, find 1 that is different in X measurements of a scale): The fact that you input some vowels and see that they are not in there, tells you that the remaining ones MUST be in the word (treating Y as a vowel as well). So it might be possible to come up with a strategy that uses that negative information as well to minimize the search space.