dissociate vs winnow out

dissociate

verb
  • To undergo dissociation. 

  • To part; to stop associating. 

  • To separate compounds into simpler component parts, usually by applying heat or through electrolysis. 

  • To make unrelated; to sever a connection; to separate. 

winnow out

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