Unless the bank has clear evidence as to who the guilty party is, the bank likely is not going to spend the time and money to find the person. The expenses involved likely will exceed $1000. The reality is that thieves usually do not have any assets that their judgment creditors can seize.
Have you been reimbursed by the bank for the lost money?
Do you know who the thief is? If you do, supply the information to the police and the bank. You may even have a civil cause of action as the known thief.
Have you checked all your belongings? Sometimes, because there are so many things in a house, people do not find out things are missing.
Have you talked with your neighbors? Perhaps the neighbors saw something.