hi there! There's now a button over by your end turn thing where you can read the clue, and a greyed one that says dig for treasure! Once you arrive within 3 tiles (that's 5x5 = 25 tiles), it'll light up!
With the "between X and Y" it's trying to find the structures most linearly opposed, so it might in fact be somewhere on the line between them. There's usually also some third bit of info
Good luck treasure hunting! You'll get the hang of it
And thanks for playing my little game :3