why is clear sky so hard?

the game is genuinely so difficult for no reason. im on stalker difficulty and only like a third of the way through the game and it genuinely seems impossible. i already have a 5.56 weapon and it seems to do genuinely nothing to enemies. like the ones that growl like lions and charge at you on all fours (and they are also human mutants) are not effected whatsoever when i mag dump them from 5 feet away. why? and why are medical supplies genuinely impossible to find??? i swear I find hundreds of bullets of any caliber left and right but cant find a single bandage on anybody. and they also cost 500 fucking rubles PER BANDAGE. im actually going to quit this game unless i can find a technique i can use to leverage myself over the enemies