sob vs waul

sob

verb
  • To say (something) while sobbing. 

  • To soak. 

  • To weep with convulsive gasps. 

noun
  • A cry with a short, sudden expulsion of breath. 

  • sound of sob 

waul

verb
  • To wail, to cry plaintively. 

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