Perhaps you should try some spelling variations:
"donauschwabisches christentum uber. 23" » "donauschwabisches schrifttum uber. 23" (Expand Search), "donauschwabisches christentum der. 23" (Expand Search), "donauschwabisches christentum eine. 23" (Expand Search)
"dopnauschwabisches schrifttum heft. 23" » "donauschwabisches schrifttum heft. 23" (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("donauschwabisches christentum uber. 23") OR ("dopnauschwabisches schrifttum heft. 23"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"donauschwabisches christentum uber. 23\") OR (\"dopnauschwabisches schrifttum heft. 23\"))*".
• Removing quotes may allow a broader search: (( donauschwabisches christentum uber. 23 ) OR ( dopnauschwabisches schrifttum heft. 23 ))*.