cajole vs soft-soap

cajole

verb
  • To persuade someone to do something which they are reluctant to do, especially by flattery or promises; to coax. 

noun
  • The act of cajoling 

soft-soap

verb
  • To attempt to persuade by flattery or pleasing words; to butter up. 

noun
  • Persuasion by means of flattery or pleasing words. 

How often have the words cajole and soft-soap occurred in a corpus of books? (source: Google Ngram Viewer )