sharp practice vs subterfuge

sharp practice

noun
  • Commercial activity that is possibly dishonest while not actually being illegal. 

  • A lawyer's unfairly taking advantage of an opposing party's missteps or inexperience to gain an advantage. 

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 sharp practice and subterfuge occurred in a corpus of books? (source: Google Ngram Viewer )