<http://schema.org/availability>
"http://schema.org/InStock"^^<http://www.w3.org/2001/XMLSchema#string>
<http://gianhangvn.com/ha-ng-agr-agr-c504-agr-mbt7200-mbt7400-agr-2012919-da-u-do-2012983-538350.html>