healer vs sangoma

healer

noun
  • One who heals, especially through faith. 

  • Anything that heals; a medicine that heals some wound, injury, ailment, or disease. 

sangoma

noun
  • A (usually female) traditional healer or herbalist, or witch doctor. 

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