disquiet vs nonchalance

disquiet

noun
  • Lack of quiet; absence of tranquility in body or mind 

verb
  • To make (someone or something) worried or anxious. 

nonchalance

noun
  • Indifference, unconcern; carelessness; coolness; disregard, detachment. 

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