Often printmaking books (and courses) have a little section on chine collee tagged onto the main subject. This may have sparked your curiosity and, like lots of printmaking techniques, you will find once you start investigating it you discover a whole world of possibility.
Combining collagraphs and mono-prints is a lovely versatile technique that I have used several times in community workshops. It works so well because it is easy to understand and people quickly get satisfying results. There is also plenty of scope for development so people with more printmaking experience enjoy playing with the two techniques together.