teachable vs willing

teachable

adj
  • Willing to receive instruction or to learn; docile. 

  • That can be taught. 

  • Capable of being taught; apt to learn. 

  • Facilitating teaching; instructive. 

willing

adj
  • Ready to do something that is not (can't be expected as) a matter of course. 

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