<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<https://celiac.org/page/4/?option=com_content&view=article&id=215%3Acdf-camp-gluten-free-directions&catid=3%3Akids-corner&Itemid=289>