unconcern vs uneasiness

unconcern

noun
  • Freedom from worry or apprehensiveness; insouciance or nonchalance. 

  • Lack of interest or care; indifference or apathy. 

uneasiness

noun
  • An anxious state of mind; anxiety. 

  • The state of being uneasy, nervous or restless. 

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