Perhaps you should try some spelling variations:
mittelb » mittel, mittelbau, mittelbis
mittelbar » mittelar, mittelbauar, mittelbisar, mittelbare, unmittelbar, ermittelbar
mittelbauar » mittelauar, mittelbauauar, mittelbisauar, mittelbarer, mittelbau, mittelbaus
unmittelbaren » unmittelaren, unmittelbauaren, unmittelbisaren, unmittelbareen, ununmittelbaren, unermittelbaren, unmittelbare, unmittelbar

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: ((mittelb OR (mittelbar OR mittelbauar)) OR unmittelbaren)*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((mittelb or (mittelbar OR mittelbauar)) or unmittelbaren)*".