shortness of breath vs sob

shortness of breath

noun
  • difficulty in breathing; dyspnea 

sob

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

  • sound of sob 

verb
  • To soak. 

  • To say (something) while sobbing. 

  • To weep with convulsive gasps. 

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