proffer vs send in

proffer

verb
  • To offer for acceptance; to propose to give; to make a tender of. 

noun
  • An offer made; something proposed for acceptance by another; a tender. 

send in

verb
  • to give (one's name), present (one's card) when making a social call 

  • to send (a batsman) on to the field to bat. 

  • to cause (something) to be delivered, especially by post/mail 

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