ax to grind vs flattery

ax to grind

noun
  • A grudge or grievance, with implications of confrontation. 

  • A proposition or point of view to advocate, especially motivated by self-interest. 

flattery

noun
  • An instance of excessive praise. 

  • Excessive praise or approval, which is often insincere and sometimes contrived to win favour. 

How often have the words ax to grind and flattery occurred in a corpus of books? (source: Google Ngram Viewer )