Check the reference tags e.g. 5EH1015678 E47 B6A8 ',05 refers to the year (2005), EH' refers to the season, that is, EtÃ© (Summer). HH refers to 'Hiver' (Winter).
'101' refers to the item group, in this case, trousers (Pantalon). Other examples: 102 refers to blazers (Veste), 105 to shirts (Chemise) and so forth.
Most dior by hedi stuff commands a nice premium