TM is a "trap card" unless there are strong enablers and/or there are no other good strategies, and in this case, an engine like your opponent made is probably the strongest option. Additionally, your Treasure Maps don't collide until your turn 14 which is TERRIBLE luck. But, it could've been prevented. You should actually be getting more than 2 T-Maps in your deck... 3 or 4 I believe? I'd pick up a couple Silvers, in order to afford more TMs, before buying Cellar with $3 to spend. Another thing to note is that you should keep track of every time you reshuffle... your TMs never collide because one is always stuck in the discard when the other one is in your hand. What I'm trying to say is Cellar wisely by lining them up with reshuffles in order to increase your chances of both TMs winding up in your hand at the same time. Don't just Cellar everything all the time.