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The folks at SEMRush spotted Google offering searches tips and tricks for searching when Google has no results to offer the searcher. So if Google has no results, it would say in this example "it looks like there aren't any great matches for your search." Then it offers a did you mean result and then other search examples, this is then followed by tips and tricks on how to search.
Here is a screen shot that SEMRush posted on Twitter (you can click to enlarge):
We spotted Google doing something similar but not without giving that searcher any tips, instead just saying "Hmm... the results for your search don't seem very relevant" and then giving other search options.
Pretty interesting...
Forum discussion at Twitter.
