1. The object of Metaphysics
We know that the object of Metaphysics is being, and you can find it in everything. Someone could think that Metaphysics studies everything, but it is not the case.
If we ask ourselves what a man is, Metaphysics will answer that he is a being, but this is not enough. Man has many qualities which their knowledge we are interested in: where comes he from, how old are he, his digestive system, his breathing system, his blood, his bones, his ideas and feelings, etc. About the man there are many qualities that are studied by specific sciences: Medicine, Psychology, etc.
Everything, besides having being, has many other qualities and attributes studied by particular sciences.