"During the on-sale period, there will be no hold-mechandise or check-inventory services."
留貨 hold mechandise (to keep a mechandise item for a customer with the expectation but not the quarantee that she will come to buy it).查貨 check inventory to look for a particular item for a customer.
During a sales event, stores will display all the on-slae items, and the customers are expected to find what they like themselves, buy and pay for the items.