Two systems in one line

Hello to all, I am working with very small scores of 2 beams. I want to put two of those scores into one line, each of them in a separate system. This means, that in the line, a new system has to begin, separated from the first one by a little horizontal space. How could I do that in

Syntax error using \midi directive

von Jörg Krause } \score { \new PianoStaff { \new Staff \VierzeiligErsterOben \new Staff \VierzeiligErsterUnten } \header { piece = 4 Zeilen