cover story vs subterfuge

cover story

noun
  • A fictitious account that is intended to hide one's real motive. 

  • A story included in a publication that is highlighted on the front cover. 

subterfuge

noun
  • Deception; misrepresentation of the true nature of an activity. 

  • An indirect or deceptive device or stratagem; a blind. Refers especially to war and diplomatics. 

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