As long as both conditions are met, otherwise only one of them can be used, such as Store A is full 100 minus 20, Store B is full 100 minus 10, Store A chooses 170 yuan products, Store B chooses 140 yuan products, and the cross-store full minus condition is full in 300 yuan. Store B is full and reduced 130 yuan. The total amount of products ordered by these two stores is 280 yuan, which does not meet the requirements of cross-store 300 yuan. At this time, the discount of cross-store full reduction will not be superimposed.