Regulations Governing the Management of Import/Export Clearance for Transportation means Article 60

The cargo carried by a vehicle entering the country shall declare to the first Customs office it arrives at along the way.
中文原文 運輸工具進出口通關管理辦法第60條
駛入國境車輛所載之貨物,應向抵達國境首先經過之海關報關。

English translation for reference only; the Chinese text prevails. Not legal advice.