Perhaps you should try some spelling variations:
"donauschwabischen schrifttum heft 3" » "dopnauschwabisches schrifttum heft 3" (Expand Search), "donauschwabisches christentum heft 3" (Expand Search), "donauschwabischen geschichte heft 3" (Expand Search)
"donauschwabisches schrifttum heft 9" » "donauschwabisches schrifttum heft 1" (Expand Search), "donauschwabisches schrifttum heft 2" (Expand Search), "donauschwabisches schrifttum heft 4" (Expand Search), "donauschwabische schrifttum heft 9" (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 9\") OR (\"donauschwabischen schrifttum heft 3\"))~".
• Removing quotes may allow a broader search: (( donauschwabisches schrifttum heft 9 ) OR ( donauschwabischen schrifttum heft 3 ))~.
• Adding a wildcard symbol may retrieve word variants: (("donauschwabisches schrifttum heft 9") OR ("donauschwabischen schrifttum heft 3"))*.