bring on vs struggle

bring on

verb
  • To pose a challenge or threat; to attack; to compete aggressively. 

  • To cause. 

  • To make something appear, as on a stage or a place of competition. 

struggle

verb
  • To strive, to labour in difficulty, to fight (for or against), to contend. 

  • To strive, or to make efforts, with a twisting, or with contortions of the body. 

noun
  • A contortion of the body in an attempt to escape or to perform a difficult task. 

  • Strife, contention, great effort. 

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