Why don't u get  masters degree like MLA or so from US University.I'v no idea about vocational training.But u can come to US in f1 visa as a student .You know Santosh Giri is also a lawyer and I think he is doing masters or already got the license or don;t know for sure.But he is also a lawyer from Nepal in US.So,just contact him.He is the right person for you to discuss about your subject and immigration.

Sorry can't help much.