The Krakonos and the Skiers (1981)

Matej and Jenda, two of the eight children of the poor Pelc family in the Giant Mountains, help in a glass works where the oldest brother Francek works. They hide into a tub not to be seen by supervisors checking on the ban of children labor. They miss the Epiphany carol (songs and treats door-to-door) and all neighbor village boys again on them in all the neighbor houses. On their way home they are passed by a fast moving big man with a large backpack. The boys send the customs officers, who are pursuing the strange man, to the opposite direction. The man then thanks them and rewards them the next day. Based on fairy-tales and legends the boys think the man is Krakonos (the giant living and ruling in the Giant Mountains).

Unfortunately the movie The Krakonos and the Skiers is not yet available on HBO Max.