@yafa @mischievoustomato use specialized search engines, not google

you want to find a book use a search engine that looks for books. go on annas-archive or zlibrary and use the filters

academic papers? there are loads of search engines focused on that. if you're in university you likely have access to loads of paywalled stuff. your student account will have some interface with the library to let you search for papers

follow chains of references. when someone mentions a book or paper in something you're reading, look it up. when you find an author you like, look up their other stuff. if they're really good find their personal blog if it exists and read everything they ever wrote

watch technical talks on youtube and take note of any books, articles, or other talks they mention. then look those up too

go to manufacturer websites in the relevant industry and read their literature. many will have training materials or white papers. same with industrial suppliers

go on topic-focused subreddits or forums and search for resource recommendations there. reddit is gay, doesn't mean every recommendation there is bad

go to an actual library in person and just look at the books on the shelves. most fields do not advance so quickly that a 30 year old book is useless, and many out of print books are not available online at all