Restrict search engines from crawling to the root directory by adding the code snippet below to robots.txt file.
User-agent: *
Disallow: /cgi-bin/
Disallow: /wp-admin/
Disallow: /wp-includes/
Disallow: /xmlrpc.php
Disallow: /wp-content/plugins/
Disallow: /wp-content/cache/
Disallow: /wp-content/themes/
Disallow: /trackback/
Disallow: /feed/
Disallow: /comments/
Disallow: /category/
Disallow: /trackback/
Disallow: /feed/
Disallow: /comments/
Disallow: /*?
Allow: /wp-content/uploads/