preen oneself on vs vaunt

preen oneself on

vaunt

noun
  • A boast; an instance of vaunting. 

verb
  • To speak boastfully about. 

  • To boast of; to make a vain display of; to display with ostentation. 

  • To speak boastfully. 

How often have the words preen oneself on and vaunt occurred in a corpus of books? (source: Google Ngram Viewer )