intertwist vs untwine

intertwist

verb
  • To twist together; to intertwine 

untwine

verb
  • To untwist the strands of (something entwined). 

  • To free (one thing that is entwined with another), disentangle, extricate. 

  • To become untwisted or disentangled. 

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