In the majority of the member states of the EU, purchases in the store are definite. Hence consumers cannot withdraw form a purchase or an order. In principle the right of withdrawal for consumers does only exist for online purchases or distance contracts.
However some traders accept the exchange or the reimbursement of products. This is a commercial practice by the trader and not a right of the consumer.
In case of a defect of the product the consumer has however the right to demand the repair, the exchange or the reimbursement of the product. However this right originates from the legal guarantee and not from the right of withdrawal.