commiserate vs understand

commiserate

verb
  • To sympathize; condole. 

  • To offer condolences jointly with; express sympathy with. 

  • To feel or express compassion or sympathy for (someone or something). 

understand

verb
  • To stand underneath, to support. 

  • To believe, to think one grasps sufficiently despite potentially incomplete knowledge. 

  • To grasp a concept fully in one's mind, especially (of words, statements, art, etc.) to be aware of the meaning of and (of people) to be aware of the intent of. 

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