mystified vs slack-jawed

mystified

adj
  • puzzled or confused 

  • state of enchantment as concerns person or event 

slack-jawed

adj
  • Unsophisticated or unthinking; dimwitted in appearance. 

  • With the mouth in an open position and the jaw hanging loosely, especially as indicating bewilderment or astonishment. 

How often have the words mystified and slack-jawed occurred in a corpus of books? (source: Google Ngram Viewer )