how to render a template inside a template? I have entity Car which has a node reference of another entity: Review

Car has a custom .tpl file node--car.tpl.php and reviews have there own .tpl files "node--reviews.tpl.php"

when i try to render the reviews of the Car inside the node--car.tpl.php the reviews does not render using their own .tpl files, 

i am using render() drupal function

can someone explain me why?

EDIT:

Heres the code which fetches the reviews: 

function mymodule_get_reviews( $nid, $full = false ) {
    $field = 'field_car_reference';
    $sql_query = 'SELECT DISTINCT entity_id AS reference FROM {field_data_' . $field . '} WHERE ' . $field . '_nid IS NOT NULL 
        AND ' . $field . '_nid = ' . $nid;

        $queryObj = db_query( $sql_query );

        $type = 'review';
        $nodes = node_load_multiple($queryObj-&gt;fetchCol('reference'));

    $reviews = array();

        if( !empty( $nodes ) )
        {       
            foreach( $nodes as $nid =&gt; $node_review )
            {
                    if( $node_review-&gt;workbench_moderation['current']-&gt;state == 'published' ) {
                        $node_review = node_show( $node_review );                                                 
                        $reviews[] = $node_review;
                    }
            }
        }        
    return $reviews;
}


the function is called as:

$reviews = mymodule_get_reviews( $node-&gt;nid );
if( !empty( $reviews ) ) {
  echo render( $reviews ); 
}
When a template is not being applied, the first thing to always check for is the filename of the template :)

Make sure it matches the machine name of the content type.