put lipstick on a pig vs smarten

put lipstick on a pig

verb
  • To superficially alter something in the hope of making it seem more appealing than it is in actuality. 

smarten

verb
  • To make smarter in appearance; to refurbish or spruce up. 

  • To increase the speed of (one's travel on foot, etc.). 

  • To augment with computer technology. 

How often have the words put lipstick on a pig and smarten occurred in a corpus of books? (source: Google Ngram Viewer )