The search page will be one of the most-used parts of any site, but what happens if the visitor's search term produces no results? Rather than simply display 'No results found', interface design consultancy Nielsen Norman Group offers three principles for designing that results page.
The basic idea is quite straightforward:
1. Clearly explain that there are no matching results. 2. Offer starting points for moving forward. 3. Don't mock the user.
The first principle requires that the message saying 'No results' is prominent, and in the location where search results would usually appear. The second means offering options such as reproducing the original query, along with suggestions on how to improve it. The third reminds developers that while humour can be useful, this might not be the best place for it.
Hit the full post for lots of examples and guidelines.
3 Guidelines for Search Engine "No Results" Pages [Nielsen Norman Group]