gymnosophist vs sadhu

gymnosophist

noun
  • One of a school of ancient Indian ascetic philosophers, reported in antiquity, who wore little clothing; a mystic. 

sadhu

noun
  • An ascetic or practitioner of yoga (yogi) who has given up pursuit of the first three Hindu goals of life: kama (enjoyment), artha (practical objectives) and even dharma (duty). 

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