Sufi vs rishi

Sufi

noun
  • A mystic Muslim; a Muslim ascetic; a practitioner of Sufism. 

rishi

noun
  • A Vedic poet and seer who composed Rigvedic hymns, who alone or with others invokes the deities with poetry of a sacred character. 

  • A Hindu sage or saint occupying the same position in India history as the patriarchs of other countries, constituting a peculiar class of beings in the early mythical system, as distinct from Asuras, Devas and mortal men. 

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