I really want to learn and find books about anatomy, but I don't know any book that teaches it without forcing me to look at naked photos. I don't mind muscles but I do NOT want to draw uncomfortable places.
How can I learn to cook without tasting??
I understand perhaps some apprehension if you see nudity as always sexual, however the human form isn't meant to be sexual in all cases. Study of anatomy is one such case.
You could focus on muscular anatomy, that would prevent the showing of the dermis and recognizable "parts".
Then it would be merely up to you to define where the dermis actually falls.
You can practice drawing people in public or ask your friends. Plenty of figure drawing classes use clothed models. Anatomy books, photographs and sculpture are good references. It is useful practice to sketch the figures you find in these places.
With Safe Search on you can search google images for "human figure" "muscle structure" "anatomy" "life drawing" etc. You may get guts and bodies but not nudity.
A few figure study/anatomy study websites have a "clothed" option. It is fairly easy to practice anatomy even when clothes are on, buy the bridgeman anatomy book too, most of it focus on the muscular part of the body, i'll leave some links for you: Figure drawing website, make sure to tick the decent models thingie One of the bridgeman books that helped me the most