disbelief vs dubiousness

disbelief

noun
  • Astonishment. 

  • Unpreparedness, unwillingness, or inability to believe that something is the case. 

  • The loss or abandonment of a belief; cessation of belief. 

dubiousness

noun
  • The state of being dubious. 

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