make known vs refrain

make known

verb
  • To announce (some information) generally. 

  • To disclose (a secret). 

refrain

noun
  • The chorus or burden of a song repeated at the end of each verse or stanza. 

  • A much repeated comment, complaint, or saying. 

verb
  • To stop oneself from some action or interference; to abstain. 

  • To abstain from (food or drink). 

How often have the words make known and refrain occurred in a corpus of books? (source: Google Ngram Viewer )