<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<https://www.vietravel.com/vn/van-hoa-phong-tuc/le-hoi-cha-chieng-cua-nguoi-thai-o-mai-chau-v1298.aspx>