This is very strange advice. I've never gotten a job from an acquaintance and am never likely to. There's a much bigger pool of jobs from people you don't know and a much better chance of a good match being made somewhere in that pool. The numbers are obviously in your favor despite the fact that people you've worked with know you're good. Its unlikely that you and people you know just happen to want to do the exact same thing at the exact same time with everyone else looking to recruit you.

I'd also feel really weird getting a job via acquaintance. Its like a kind of nepotism I don't want or need.