To check the approved use of an HDB shophouse, you can refer to the Grant of Written Permission issued by URA. A copy of this document can be obtained from the landlord or the property owner. Alternatively, you can submit a search enquiry to URA, which involves a search fee of S$53.50 (including GST) per property unit, and the result will be received within 2 weeks. URA also offers a free Electronic Development Register to check for approved use.
For more information, you can visit the URA website
here.