What is the name of the game?
 

What is the name of the game they play and does someone has more of them this set?

This is called "Löffelspiel" (spoon game) or sometimes "Verbundenheit" (connectivity), as there are several spoon games...
A string is tied to a spoon and then threaded through everyones clothes. (And to be honest, showing undies is not necessarily part of that game, although making it much more fun :D ).
This one is being played on a playground in Essen, Germany.