This is not possible with the magic methods, however you can achieve this using DQL (Doctrine Query Language). In your example, assuming you have entity named Orders with Product property, just go ahead and do the following:
$dql_query = $em->createQuery("
SELECT o FROM AcmeCodeBundle:Orders o
WHERE
o.OrderEmail = 'some@mail.com' AND
o.Product LIKE 'My Products%'
");
$orders = $dql_query->getResult();
Should do exactly what you need.