Shadow library creators assembled them because educational resources are punitively expensive in many parts of the world. Unlike warez and other sketchy download sites you won't see bullshit adverts etc.

Example parent link. z-lib has a decent variety of manuals but not a lot of HD stuff. General search terms like "service manual" are a good way to begin.

Example ebook: is another good one. because science and technology are about more than just choppas.

WAY more background than even I give a shit about but those curious can get a basic idea why shadow libraries are expanding. Anyone still in school would benefit by getting familiar:


When the resource is an ebook you can use Calibre and other tools to convert it to .pdf for convenient reading on any device.