Hi Kinson,
I can't speak for your translation, but can answer your questions.
A "crash course" is a course that covers a lot of information in a short period of time; condensed. Example: Instead of the normal time frame of 8 weeks it might cover a few days, or 4 weeks.
This article is saying that you will get valuable (precious) contacts, of recruiters who can assist you in many ways. Like the contacts could be like "precious stones" because of information they could provide for you.
Hope this helps!