talk about vs talk over

talk about

verb
  • Used other than figuratively or idiomatically: see talk, about. (Compare discuss.) 

  • Used to draw attention to the speaker's approval or affirmation of someone or something 

  • Used to draw attention to the speaker's characterization of someone or something 

talk over

verb
  • To discuss; to converse about a matter or issue. 

  • To persuade (someone); to talk around. 

  • To verbally interrupt (someone); to speak at the same time as someone else. 

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