Google search result

How do I get my site to look like this on Google search

Is there a manual somewhere ? 

learn how to use SEO for your site.
plus add content to your site... that will rank you better.

Google does that automatically... It takes time, and I think the sitemap might help.

I generated the sitemap but it also generates pages which I don't want to show on Google, so I edited the robots.txt file.

Don't really know how to add content to my site, so I guess I have to go digging on the internet again and learn about SEO :-)

They are called sitelinks.

Google's official Sitelink info can be found here:
https://support.google.com/webmasters/answer/47334

You can find a section in Google Webmaster Tools as well:
Google Webmaster Tools
-Search Appearance
--Sitelinks

Sitelinks just happen. Nothing you do for it. The trick is that Google only shows them when they are sure that the site is an absolute authority for the keyword. In your example, they were sure that our site is most definitely relevant to "boonex" search query and decided to show as much useful information about our site as possible. 

thanks for the info, it already clarifies a lot :-)