Thanks, CCC. I guess she should not disclose the intention of coming here to see me in order not to draw any suspicion of immigration intentions. Is traveling/sight-seeing a better reason than coming here to see someone say, a classmate or a distant relative.
if your gf have full time job and salary above 25k/year(proved by the employer letter)she should easy get 5-10 years travel visa.
if she doesn't have job yet, that's hard to say how long.