I think it is safe to say that she is not chopping lettuce with a bunch of Mexicans Farm workers. From what I gather, her university was in session and she was AWOL. Sounds like she was dropping out. Perhaps rather than just tell her parents, she pulls a disappearing act.
I think there is a long tradition in Canada of heading down to the States to "start over". Immigration isn't as easy as it used to be but they manage. California and Florida seem to be primary destination because of the weather. There is also a large Chinese/Cantonese community that she could link up with in the greater LA area.
There is, of course, the possibility that she has befallen victim to a crime, but if she was dropping out of the University in defiance of her parents expectations, there is a good chance she is an "adult runaway".
Sexual predators who abduct and murder women rarely go to great lengths to conceal the victim's body unless they have ties to that victim or can otherwise be linked. The longer she remains missing, the more likely she is OK.