set on vs tenacious

set on

verb
  • To attack. 

  • To be determined to do or achieve something. 

  • To encourage someone, or an animal, to attack someone. 

tenacious

adj
  • Unwilling to yield or give up; dogged. 

  • Having a good memory; retentive. 

  • Holding together; cohesive. 

  • Clinging to an object or surface; adhesive. 

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