qualm vs suspicion

qualm

noun
  • A prick of the conscience; a moral scruple, a pang of guilt. 

  • A feeling of apprehension, doubt, fear etc. 

  • A sudden sickly feeling; queasiness. 

verb
  • To have a sickly feeling. 

suspicion

noun
  • The act of suspecting something or someone, especially of something wrong. 

  • Uncertainty, doubt. 

  • The imagining of something without evidence. 

  • A trace, or slight indication. 

  • The condition of being suspected. 

verb
  • To suspect; to have suspicions. 

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