Google is typically only good for finding small snippets of code or open-source libraries. Documentation for some libraries/programs is unreliable at best (if it exists, it only shows you simple or common examples.)
I don't have many programming books, but I can tell you right now that I've got a book about OpenGL, and it's got the majority of the code for a 3D engine in it, which you can simply copy, but you can read the theory as well -- you just have to turn a few pages and an explanation of the code is right there, waiting to be read. Nowadays, you could probably find some open-source 3D engines on the net, but if you need to change the code substantially, you're probably in some trouble -- typically no help forum exists and the people on SO won't know the answer to your question if it's very specialized. When it comes to really specialized stuff, only a few dozen people in the entire world are going to be able to answer your question without spending hours in order to figure out enough to be in a position to come up with an answer. If you ask how to implement a linked list in C#, you're going to get 5+ answers on SO in the first 10 minutes, but if you ask what the best way to go about implementing a complex shading algorithm in three.js is, your question is going to sink off the front page like a rock.
On top of that, books are written almost exclusively from the perspective that the reader wants to learn about the theory involved, whereas google just produces random junk -- code snippets, archived discussions about the subject in which nobody knows what they're talking about, etc. Sources on the internet have gotten a lot better: SO, Moz Dev Network, Microsoft's web site, blogs, etc., but historically, books have been much better, with internet sources just now catching up.