1. Log in to Haidian system, find the "Inventory Management" option in the left navigation bar, and click Enter.
2. On the inventory management page, you can see the detailed information and related information of all the goods in stock, including the shelf life and sales period. Find the drug to be adjusted, and click to enter the detailed page.
3. After entering the drug details page, you can see the detailed information of the drug, including inventory quantity, shelf life and sales period. To adjust the date of selling medicine, you can click the "Edit" button.
4. In the editing page, you can modify various parameters of drugs, including shelf life and sales period. Find the date parameter to be adjusted and modify it.