Hi,
to filter the items by user, you first have to put a relationship between the user and the item entities, then, when you save the item, you should also connect it to the logged user (with a connect component or directly by passing the oid of the user to the relationship binding when saving the information of the item).
At this point you'll have the item with the information of the user who saved it, so you just have to add a relationship role condition to your list, select the relationship between the item and the user, and then pass the UserCtxParam (containing the oid of the user) to the condition with a get component.
I hope this helps!