If arriving at the airport you do not find your luggage, you should immediately inform the serving stuff of baggage tracing service or representative of the relevant airlines at the airport. This must be done in order to entrench an official request for baggage tracing.
You will be given a corresponding receipt of lost of luggage indicating its number and date. The receipt should be saved because you will need it in the future. Be sure to check that there was a right contains the information about baggage weight, airlines, your personal data (name), your contact details and coordinates, the date of issuance of certificate, check the number against listed in the documents with the number on the luggage tag portion which is taped on the cover of your plane ticket (this is the most important thing that should be mentioned in the documents).
Keep all the boarding passes from the start of the trip until the very end with all transit stops.
After the registration of all necessary documents for lost luggage and arrival into the customs control zone of the customs authority (including the entry into the territory of the Republic of Belarus if you go by road or rail) you should obligatory fill the passenger customs declaration in 2 copies in respect of goods transported in accompanied baggage, putting the mark about unaccompanied (lost) luggage. On arrival from abroad the incoming luggage for free circulation is provided to the customs authority by the declarant, the carrier or other authorized person. Customs official registers an advance declaration, confirms the information which was given by the declarant and makes decision about possibility of producing such goods.
If during customs control in the incoming luggage from abroad there are goods which are either prohibited or have restrictions on import and (or) shall be payable customs duties in respect of all goods contained in the incoming luggage from abroad, customs authority refuses the release of such goods.
Please, note that if a natural person in the case of lost of luggage fill did not fill the passenger customs declaration filled in respect of goods transported in accompanied baggage, arrived luggage to him for customs purposes will be considered as imported in excess of the norms of duty-free admission and it will be necessary to pay due customs duties and taxes.