observe vs strive

observe

verb
  • To follow or obey the custom, practice, or rules (especially of a religion). 

  • To take note of and celebrate (a holiday or similar occurrence); to follow (a type of time or calendar reckoning). 

  • To notice or view, especially carefully or with attention to detail. 

  • To comment on something; to make an observation. 

strive

verb
  • To struggle in opposition; to be in contention or dispute; to contend; to contest. 

  • To try to achieve a result; to make strenuous effort; to try earnestly and persistently. 

  • To vie; to compete as a rival. 

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