$args = array(
'limit' => 50,
'return' => '*',
'status' => 'wc-completed',
'event_name' => $filter_event_names,
'start_date' => array($eventStarteDateFrom, $eventStartDateTo),
'start_time'=> $filterEventTime,
'meta_key' => 'start_date',


);
$query = new WC_Order_Query($args);
//////////////////////////////////

function handle_custom_query_var($query, $query_vars)
{
if (!empty($query_vars['event_name'])) {
$query['meta_query'][] = array(
'key' => 'event_name',
'value' => $query_vars['event_name'],
'compare' => 'IN',

);
}
if (!empty($query_vars['start_date']) && isset($_GET['event_start_date']) && !empty($_GET['event_start_date'])) {
$query['meta_query'][] = array(
'key' => 'start_date',
'value' => $query_vars['start_date'],
'compare' => 'BETWEEN',
'type' => 'DATETIME'

);
}
if ( ! empty( $query_vars['start_time'] ) ) {
$query['meta_query'][] = array(
'key' => 'start_date',
'value' => $query_vars['start_time'],
'compare' => 'LIKE',
'type' => 'TIME'

);
}


else{

}


return $query;
}
add_filter('woocommerce_order_data_store_cpt_get_orders_query', 'handle_custom_query_var', 10, 2);