<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.cambodiaun.org/?view=article&catid=104%3Abulletin2011&id=204%3Aaugust-2011-bulletin-vol60&format=pdf&option=com_content>