explain vs interweave

explain

verb
  • To make something plain or intelligible. 

  • To make plain, manifest, or intelligible; to clear of obscurity; to illustrate the meaning of. 

  • To give a valid excuse for past behavior. 

interweave

verb
  • To intermingle. 

  • To combine through weaving. 

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