I have this book, which is actually targetted to vets, but it has a ton of details with good descriptions -
It does not discuss husbandry in great detail though, there are other books for that. It will explain you how certain behaviors/illnesses are related to improper husbandry.
It goes down to the level of performing surgery, so I guess that is way beyond what you look for.
It will also tell you how to do a physical examination of any reptile or amphibian, what signs to look for, which steps should be taken in case any test fails, which illnesses may be associates to it, etc etc etc. It's rather extensive.