Heavenscent

Hello, I am a little confused with the new update and the locations! I did read again today and tried some of the farm spots but i am not sure if i understand correctly! First of all, i would like to ask if spellbooks are given only from class change or can be farmed as well based on the wiki locations! Secondly, i noticed that some locations have extremely low xp. I refer mostly to enchanted valley and death pass which i did use in the past to level main and 2 supports. Now on solo you get 9-12k each which i think is extremely low. Which means that when you hit 50 lvl xp drops dramatically? Am i missing something here? If i want to craft a yaksa or an fp set which are the locations to farm? I am completely confused! I killed 100 monsters in EV and i received only adena. Kind regards,