1. A method for inspecting a vehicle, comprising steps of: Acquiring a unique identity number of an inspected vehicle; carrying out X-ray scanning on the inspected vehicle to acquire an X-ray image of the inspected vehicle; retrieving at least one historical inspected image related to the unique identity number from a historical inspection database; determining, based on one template image selection algorithm selected from multiple template image selection algorithms, one of the at least one historical inspected image as a template image; determining a difference region between the X-ray image and the template image; and presenting the difference region to a user.