Perhaps you should try some spelling variations:
"johannes gardiner muller" » "johannes gartner muller", "johannes gagnier muller", "johannes gantier muller", "johannes armiger muller", "johannes rainer muller", "johannes gardner mcmullen"
"johannes dietmar muller" » "johannes dieter muller", "johannes dietlein muller", "johannes der muller", "johannes dietmar walter"

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: (("johannes dietmar muller") OR ("johannes gardiner muller")).
• Removing quotes may allow a broader search: (( johannes dietmar muller ) or ( johannes gardiner muller )).
• Adding a wildcard symbol may retrieve word variants: (("johannes dietmar muller") or ("johannes gardiner muller"))*.