When my mini was th9, I pushed to champs league (for the gem reward) using lavaloonian.
With that strat, most th9s can be crushed, but not all. There are some really good anti-air th9 bases I've seen.
My advice: learn lavaloonian and/or dragloon for th9.
Also, learn a good ground strat such as hogs, or gowivalk (or use pekkas instead of golems).
Also, learn how to scout a base to determine if it is anti-air. I learned what kinds of bases are anti-air the hard way: attacking them with an air army and either failing (0 stars) or getting 1 star.
I'd warch the replays and see how the base was designed.
After learning the hard way multiple times, I've learned to recognize anti-air base designs.
This has helped me on my th13 too.
