The set of 5 stamps on the left represents traditional games. The 2 stamps in the middle were issued for the Journée du Timbre 1967 and 1966. They both illustrate postmen delivering their mail. Finally, the stamp on the far right portrays Paul-Emile Janson (1872-1944), a Belgian liberal politician who served as the 30th Prime Minister of Belgium in 1937-1938.
Thank you Thomas! ;-)