I don't want to discourage you, but your chances of being able to work in the US as a CFI are very slim. As another poster already stated, you need to be a citizen or have some kind of work visa.
Work visas are typically alloted to those who meet a certain criteria. A CFI, is not one of those particular skills.
Permanent Workers | USCIS
If your dream is to work in the US, my advice to you is to get out of aviation and get a PhD.
I would gladly trade my aviation career in the USA, for yours in SE Asia. The money sucks here. I sometimes have to justify buying lunch.
Good Luck