Search engines will automatically only pickup all content when you create pure HTML WebHelp or 508 compliant output. For all other outputs, you need to provide a sitemap. This is also true for Responsive HTML5.
Just creating a sitemap is not enough, as you also need to register the sitemap with the search engine. It won't pick up the site map automatically. All major search engines have detailed instructions on how to submit site maps.
I have a script to generate site maps for help (Sitemap generator | WvanWeelden.eu) - commercial script - and I post those site maps to search engines.
Kind regards,
Willam
