seo - Disallow: /sites/default/files/ not working for my Drupal Website -

seo - Disallow: /sites/default/files/ not working for my Drupal Website -

i working on drupal 7 website. added next robots.txt file (under # directories section)

disallow: /sites/default/files/

but when type "site:www.example.com filetype:pdf" in google, still able crawl /sites/default/files folder. please help me figure out why these still beingness crawled?

the relevant link got here was: can add together sites/default/files in robots.txt? not reply question.

remember google's cache valid 2 weeks settings affective after time period.

drupal-7 seo robots.txt google-search