Perhaps you should try some spelling variations:
"mathematisches problem" » "mathematische problem", "mathematischer probleme", "mathematische probleme"
"pragmatisches problem" » "praktisches problem", "politisches problem", "statistisches problem"
"pragmatic problem" » "pragmatic program", "problematic problem", "diaphragmatic problems"

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: (("pragmatic problem") OR ((("pragmatisches problem") OR ("mathematisches problem")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"pragmatic problem\") or (((\"pragmatisches problem\") OR (\"mathematisches problem\"))))".
• Removing quotes may allow a broader search: (( pragmatic problem ) or ((( pragmatisches problem ) OR ( mathematisches problem )))).
• Adding a wildcard symbol may retrieve word variants: (("pragmatic problem") or ((("pragmatisches problem") OR ("mathematisches problem"))))*.