Changing second profession---skills?

Alright guys I did a search and wasn't able to specify it enough to find anything so I'll ask quick.

I'm thinking of changing my secondary profession, when you change it in the desert I understand you lose all your previous secondary profession skills for that character. How do you get the skills for your NEW profession? Do you simply go back to ever skill trainer and buy them? If this be the case, then you'd need many skills points to unlock them all yes? ---Thanks.

You can buy them from a trainer or you can do profession-spedific quests that give skill rewards.

There's only a few of those for each profession though, so basically yes you have to buy almost all of them.