shaman vs theurge

shaman

noun
  • A traditional (unscientific) faith healer. 

  • A member of certain tribal societies who acts as a spiritual and, or religious medium between the concrete and spirit worlds. 

theurge

noun
  • One who works miracles, or persuades a god or spirit to perform a supernatural work. 

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