Result page for Search box

Jesper...you can accomplish this with a Content Search web part and the KQL query provided.  Here are the steps I used to repro the solution:

1. Create a new Web Part Page.
2. Add the Search Box and Content Search web parts to the page.
3. Make sure the Search Box results are pointing to the Content Search web part.  It should do this automatically.
4. In the properties of the Content Search web part -> Change Query button -> Advanced View to see the KQL editor.
5. Paste in this KQL:  "path: http://....../.../search/{SearchBoxQuery}"
6. Save and test.

Assumptions:

• When the user types in something in search box, whatever they type in will get appended to the end of the "path" url in the KQL search string.
• In my testing whatever I typed in the search box was a site that I wanted to focus my search to. 
• In your example I assumed amsterdam was the name of a site you wanted to focus your search results to.
• The Content Search web part will return results specific to the "path" in the KQL query.

Hopefully this is what you're looking for.

Steve