changeable vs undisturbed

changeable

adj
  • Capable of being changed. 

  • Subject to sudden or frequent changes. 

  • Capable of camouflaging itself by changing colour. 

undisturbed

adj
  • not disturbed or agitated 

  • calm 

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