contemplate vs thresh out

contemplate

verb
  • To look at on all sides or in all its aspects; to view or consider with continued attention; to regard with deliberate care; to meditate on; to study, ponder, or consider. 

  • To consider as a possibility. 

thresh out

verb
  • To extract or remove by threshing. 

  • To thrash out. 

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