My luggage contained 4 batteries and it was seized by Guangzhou baiyun airport's custom officers and it has not been returned. what should i do?

You mean they are seized by the officers when you take airplane out of China?
If so, you may try to contact the airport custom officer directly and their phone number is 020-36066581.
As I know, there is limitation on the batteries' carrying. Usually, No more than two 100Wh-160Wh spare lithium- ion batteries may be carried in carry-on baggage by each person and you should get the approval from the airline company.
For portable eletronic devices, you do not need to get approval, but you are not allowed to take much.