My gf got her USA 10 years visa in bkk : Bank statement 600k , monthly income + salary slips , purchased condominium title deeds , family photo…. And more , but those are most important.
As long as you can make them believe you will come back after your journey, and can afford the trip. Then you will get a visa
I don’t think there is much option for you, if you found a proper job then possible for employer switch to Non-B within Thailand. But not all employer can do this , totally depends on their abilities.
Jin had a good example, went to Cambodia , get a new TR visa. Then you can easily switch to ED or Non-B without any problem. Duke language school have good offer with ED visa ya
And for me, a few months later I’m leaving Thailand and heading to Cambodia for TR visa too.
If you still in Thailand , since last week embassy of PRC are issuing 30 days extension letter free to Chinese citizen , even Visa on arrival . Sample :