About ten days ago, Google revamped their search within a site feature and renamed it Sitelinks Search. They also gave webmasters a way to communicate that they have an internal search that should be used when using the Sitelinks search.
We already discussed some myths around it but now Google's Mariya Moeva shared some of the more common technical implementation issues they've seen when webmasters have used the SearchAction schema markup.
These issues include:
(1) If you replace the curly braces and all that's inside of it with a search term, it'll lead to a valid URL on your site. For instance, if your "target" value is "http://www.example.com/search?q={searchTerm}", please make sure that "http://www.example.com/search?q=foo" and "http://www.example.com/search?q=bar" both lead to search result pages about "foo" and "bar".
(2) The "query-input" field must point to the string that's inside the curly braces in the "target" field. For example, if your "target" value is "http://www.example.com/search?q={searchTerm}", you must use "searchTerm" as the "name" within "query-input".
Don't make these two basic but common mistakes.
Forum discussion at Google+.