Perhaps you should try some spelling variations:
"dopnauschwabisches schrifttum heft 10" » "donauschwabisches christentum heft 10" (Expand Search), "dopnauschwabisches schrifttum heft 12" (Expand Search), "dopnauschwabisches schrifttum heft 19" (Expand Search), "dopnauschwabisches schrifttum heft 30" (Expand Search)
"donauschwabisches schrifttum heft 1" » "donauschwabisches schrifttum heft 3" (Expand Search), "donauschwabische schrifttum heft 1" (Expand Search), "donauschwabischen schrifttum heft 1" (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"donauschwabisches schrifttum heft 1\") OR (\"dopnauschwabisches schrifttum heft 10\"))~".
• Removing quotes may allow a broader search: (( donauschwabisches schrifttum heft 1 ) OR ( dopnauschwabisches schrifttum heft 10 ))~.
• Adding a wildcard symbol may retrieve word variants: (("donauschwabisches schrifttum heft 1") OR ("dopnauschwabisches schrifttum heft 10"))*.