apply vs touch upon

apply

verb
  • To pertain or be relevant to a specified individual or group. 

  • To make use of, declare, or pronounce, as suitable, fitting, or relative 

  • To address; to refer; generally used reflexively. 

  • To lay or place; to put (one thing to another) 

  • To put closely; to join; to engage and employ diligently, or with attention 

  • To submit oneself as a candidate (with the adposition "to" designating the recipient of the submission, and the adposition "for" designating the position). 

  • To put to use; to use or employ for a particular purpose, or in a particular case 

touch upon

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