Two doubts.
1. How come there is no investigation into Giorgia's disappearance from her first psychiatric hospital ?
2. How does Mirella find out Matteo's home address?
1. There was. But, it s not shown on screen. Obviously, she ends up back there after the policemen catch her and may be she gets transferred to the hospital where Nicola inspects after some time. It is minute detail that the filmmakers leave to you to make something up.
2. She calls the Head office of the police dept. after she misses Matteo's call. They must have given her the information needed.
These pretzels are making me THIRSTY...