expressionlessness vs sunyata

expressionlessness

noun
  • The state of being without an expression. 

sunyata

noun
  • Emptiness, the absence of an intrinsic essence or nature which is stable and separable from other things. 

  • Emptiness, in terms of a meditative state; an Eastern concept of a high meditative state of calm and freedom from distraction. 

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