Hi,
In the file administrator/components/com_hikashop/classes/widget.php you can change the code:
if($widget->widget_params->content=='products' || $widget->widget_params->content=='categories'){
$filters=$this->_dateLimit($widget, $filters, $date_field);
}else{
$filters[]='order_discount_code IS NOT NULL AND order_discount_code <> \'\'';
}
to:
$filters=$this->_dateLimit($widget, $filters, $date_field);
if($widget->widget_params->content=='discounts'){
$filters[]='order_discount_code IS NOT NULL AND order_discount_code <> \'\'';
}