1. Search online: Use a search engine, such as Google or Baidu, and enter "Shangdu Wholesale Potato Starch" and the name of the relevant city or region in the search field, and you may find the contact information of relevant wholesalers or suppliers.
2. Associates or wholesale markets: Associates or wholesale markets usually have relevant business directories or contact information of suppliers. You can consult relevant institutions or go to their websites for more information.
3. Ask a business partner or colleague: If you have a partner or colleague in this industry, you can directly find the contact information of the supplier who wants to wholesale potato starch. They may share some useful information.
4. Online social platforms: On social media platforms, such as LinkedIn, Facebook or WeChat, join groups or circles in related industries and ask questions to group members. They may provide some suggestions or contact information.
No matter which way you use, please make sure that you have enough communication and understanding with suppliers to ensure that the suppliers you find have reliable sources and good business reputation.