First, you must find out what category your imported stuffs are under. Then find out the tax amount if there are any.

If the amount involved is very little then just pay the tax. No point arguing with those people.

If the amount is a lot, then you can get some "agents" to help you "bypass" tax. There are these people who specialize in handling imports for you. Of course you need to pay them also but it should be less than the tax amount.