The display of additional information is carried out by displaying all information (within one of the mentioned above areas) which is assigned to the nomenclature code entered as a criterion. When, for example, code 0101 00 00 00 has been entered and additional information area "Legal notes" selected, the browser displays all legal notes assigned to the code 0101 00 00 00. Only the additional information valid for the entered validity date is displayed. If for example user inserted in the nomenclature code field Chapter “5002” and selects Explanatory notes in the additional information and clicks the button “Search additional information” then system displays a link “Uwaga do pozycji 5002 ” and if user clicks on that link system displays the content of explanatory notes of chapter 5002.