magus vs printer's reader

magus

noun
  • A magician; (derogatory) a conjurer or sorcerer, especially one who is a charlatan or trickster. 

  • A Zoroastrian priest. 

printer's reader

noun
  • Synonym of proofreader 

How often have the words magus and printer's reader occurred in a corpus of books? (source: Google Ngram Viewer )