If I lie to you that I borrowed 30 thousand to drive a car and there is no such thing, then I am suspected of fraud

The main problem now is not a civil dispute or fraud, but that you need to find this person, because the police force is limited, and sometimes it is a civil dispute or fraud, which may not be clear. There are too many such things, and your 30 thousand is really not a big sum in it. You don't have to expect the police to come to you unless she does it again. If you find her, call the police. If she can be found with fixed property, it is better to sue directly, apply for property preservation and enforce it.