VAT is not recoverable on things you consume in-country , i.e., hotel, food, car rental. You have to leave the country with the merchandise in order to claim a VAT refund. Which means that you have to 1) Get a VAT refund form from the merchant(s) from whom you bought the merchandise. 2) At the airport, go to the VAT refund counter, show the agent your merchandise, and submit your form. Which means you cannot pack the merchandise in your checked luggage. Every country has different rules as to how much you have to spend in order to get a refund, if the purchases have to be at the same store, and if they have to be on the same day. Frommer's guidebooks do a good job of explaining it all. Or just ask a sales clerk at a store that displays that country's VAT refund logo.
Some stores will ship the merchandise direct to your home AND take care of the VAT form. This is because if they ship to the US, the merchandise has left the country immediately, qualifying it for a refund.