go steady vs importune

go steady

verb
  • To date one person regularly and exclusively. 

importune

verb
  • To bother, irritate, trouble. 

  • To harass with persistent requests. 

  • To approach to offer one's services as a prostitute, or otherwise make improper proposals. 

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