give weight vs substantiate

give weight

verb
  • To improve the credibility or legitimacy of. 

  • To attach importance to. 

substantiate

verb
  • To verify something by supplying evidence; to authenticate or corroborate 

  • To give material form or substance to something; to embody; to record in documents 

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