Its almost impossible for them to come to America on a tourist visa unless they are extremely wealthy and can prove their income , own property etc. I’ve tried 3 times and she has been denied within seconds. If you ever see Vietnamese traveling in America they are very rich. I would do anything to have her visit my dad minus marriage. She can’t even come on an arranged tour. Still denied. It’s bullshit because she has no desire to come and stay there. They need to make sure they will return.