1. Find the relevant documents reserved when buying a car, such as the car purchase contract and the copy of the invoice. The invoice for car purchase will be provided by the seller when buying a car.
2. If you can't find a copy of the car purchase invoice, you can contact the seller or the customer service department of the car manufacturer to provide relevant information about the car purchase (such as the car purchase time, model, seller, etc.). ) and ask the customer service department for the specific number of the car purchase invoice.
3. If you use financial loans or leasing services when buying a car, you can also contact financial institutions or leasing companies to consult the company about car purchase invoices.