bemoan vs mourn

bemoan

verb
  • To moan or complain about (something). 

  • To be dismayed or worried about (someone), particularly because of their situation or what has happened to them. 

mourn

verb
  • To utter in a sorrowful manner. 

  • To express sadness or sorrow for; to grieve over (especially a death). 

  • To wear mourning. 

noun
  • Sorrow, grief. 

  • A ring fitted upon the head of a lance to prevent wounding an adversary in tilting. 

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