suggest vs warn

suggest

verb
  • To cause one to suppose (something); to bring to one's mind the idea (of something). 

  • To explicitly mention (something) as a possibility for consideration, often to recommend it 

  • To imply but stop short of explicitly stating (something). 

warn

verb
  • To make (someone) aware of impending danger, evil, etc. 

  • To notify or inform (someone, about something). 

  • To caution or admonish (someone) against unwise or unacceptable behaviour. 

  • To give warning. 

  • To summon (someone) to or inform of a formal meeting or duty. 

  • To advise or order to go or stay away. 

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