obeah vs voodooism

obeah

noun
  • A form of folk magic, medicine or witchcraft originating in Africa and practised in parts of the Caribbean. 

  • A magician or witch doctor of the magic craft. 

  • A spell performed in the practice of the magic craft; an item associated with such a spell. 

verb
  • To bewitch using this kind of folk magic. 

voodooism

noun
  • A religious cult, from Haiti, involving witchcraft and sorcery. 

  • Any voodoo practice. 

How often have the words obeah and voodooism occurred in a corpus of books? (source: Google Ngram Viewer )