You gotta know people working in US, unfortunately. Even if you are good, people usually wouldn't sponsor you if they don't know your personality because you may become a huge liability to the company because of who you are and not because of your knowledge. Once they sponsor you, they consider you will be with them at least 5 years, that's a huge decision for a company. They gotta trust who you are. Or you gotta be uniquely great.
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