sorcery vs völva

sorcery

noun
  • Magical power; the use of witchcraft or magic arts. 

völva

noun
  • In Old Norse society, a female practitioner of magic divination and prophecy. 

  • Any prophetess, sooth-sayer, or witch. 

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