1. Multi-channel procurement: establish cooperative relations with many suppliers to obtain stable supply of different products. This can include cooperation with wholesalers, manufacturers, distributors and farmers.

2. Regular inventory management: according to the sales data and seasonal demand, make a regular inventory management plan. This helps to avoid overbought or out of stock.

3. Forecasting and ordering system: Advanced inventory management and purchasing software is used to forecast according to historical sales data and market trends, so as to determine when to order products and order quantities.

4. Standby suppliers: establish the relationship of standby suppliers to deal with the problems or shortages of major suppliers. This helps to reduce risks.

5. Supply chain diversification: consider diversifying the supply chain, including local, domestic and international suppliers, to reduce the risk of regional or global supply chain problems.

6. Establish a good relationship with suppliers: maintain a positive cooperative relationship with suppliers, build trust, and ensure support and flexibility in an emergency.

7. Supply monitoring: regularly monitor the inventory level and sales trend, and timely adjust the procurement plan to ensure the balance between supply and demand.

Through the above strategies, you can better manage the product supply of collective stores, ensure diversity and stability, and meet the needs of customers.