<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.audible.com/pd/Radio-TV/Cabin-Pressure-The-Complete-Series-4-Audiobook/B00BLRB4VU?ref_=pd_rsp_tl_1>