Perhaps you should try some spelling variations:
mittelbar » mittelbare, unmittelbare
ermittelbar » ermittelbare, erunmittelbare
unmittelbar » unmittelbare, ununmittelbare
ununmittelbaree » ununmittelbareee, unununmittelbareee, unmittelbare, unmittelbaren, unmittelbarem
unmittelbareer » unmittelbareeer, ununmittelbareeer, unmittelbareren, unmittelbare, unmittelbaren
unmittelbarer » unmittelbareer, ununmittelbareer, unmittelbare, unmittelbaren, mittelbare
mittelbis » mittelbaus, mittelbau

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((mittelbar OR ((ermittelbar OR unmittelbar) OR (ununmittelbaree OR (unmittelbareer OR unmittelbarer)))) OR mittelbis).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((mittelbar or ((ermittelbar or unmittelbar) or (ununmittelbaree or (unmittelbareer OR unmittelbarer)))) or mittelbis)".
• Adding a wildcard symbol may retrieve word variants: ((mittelbar or ((ermittelbar or unmittelbar) or (ununmittelbaree or (unmittelbareer OR unmittelbarer)))) or mittelbis)*.