php pdo loops

Attached file:

This objct is defined in the xml file being imported:
$orderdesc2 = (string)$obj->body->ORDER->ORDERHEAD->FUNCDESC;

I have just noted that the data  in the xml file is repeated but the insert command I have only inserts once. Please can someone show me how to insert a loop for this variable
such that it inserts the total number of records for that variable from the xml file into the database

Insert statement:

$stmt = $dbh->prepare("INSERT INTO retailers (ret_name, ret_add, ret_add2) VALUES (:name, :orderdesc, :orderdesc2)");


$stmt->bindParam('name', $name);
$stmt->bindParam('orderdesc', $orderdesc);
$stmt->bindParam('orderdesc2', $orderdesc2);

//execute the query
$stmt->execute();
xmlimport-form.php