How do I get search to pick up on the "&" (ampersand) character in article titles and text? The search will yield results on tags that include the "&" but not yield results if the ampersand is in the actual title or body of the article.
Lithium OOTB search works as expected. If you would like to achieve a similar behavior via API, then you must replace the special characters with their respective HTML entity name before search.
For example, if your search string includes '&' as in the message title 'Verify & validate', then your API should be something like this -
Hope this helps!