How to find by code elements to update in Event Receiver ItemUpdated and to update them ? Please help.
they are already updated, thats why the event-receiver is triggered.
you can get the item, on which behalf the receiver is running by
(properties-object is received as parameter of the method)
however, if you update the item again, you have to be careful. because updating the item again of course triggers the Events again, this could get quite complex. Reconsider your architecture before doing so.