dossier vs text file

dossier

noun
  • A collection of papers and/or other sources, containing detailed information about a particular person or subject, together with a synopsis of their content. 

text file

noun
  • A data file containing only plain, human-readable text, distinct from documents with embedded formatting 

  • A data file in a character encoding that allows it to be read in non-specialised text editor. 

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