is there any book where i can know Mehr about Fantasy creatures like what do they like and etc ?

Try searching for Bücher about folklore and legends. Fairies, myths, mythology and stuff like that.
I have noticed that there are differences in Antwort to those types of Fragen depending on the answer source. As an example, elves oder Meerjungfrauen may have different descriptions and qualities from Celtic lore to Viking oder Eastern lore.
Hope that helps.