My friend was harassed anonymously. Is there any way to trace the anonymous person?

it's not easy to check. It won't help if you just call the police for harassment. He can use Tencent's mobile phone housekeeper, which has the function of harassment interception. By choosing the interception mode, he can intercept calls in the blacklist, as well as some real estate advertisements, insurance intermediaries and other calls, as well as the anti-harassment mode at night and the spam message cloud interception function, which is very convenient to use and can keep everyone away from all kinds of harassing calls and messages.