Occult reflects knowledge and experience with the paranormal and supernatural.
It can be used to decipher strange pictograms, recall information about supernatural creatures, remember cures for monstrous maladies like lycanthropy or vampirism, or perform rituals.
Finding information in a library, newspaper morgue, old tome, the internet, etc., uses the Academics skill. As noted there, however, if the investigator’s Occult skill is higher she may use that instead.