Drupal 7 Search files : does not index the name of the files

Drupal 7 Search files : does not index the name of the files

I have installed Search Files with PDF capabilities in Drupal 7.2 It works
well, it indexes the content of the PDF files (when they contain text).
However, it does not index the name of the file itself.
For example : NEW_ADDED_FILE_12345.pdf I would like the engine to index
the content of the file, BUT ALSO : NEW, ADDED, FILE, 12345
Thank you for your kind help.