Perhaps you should try some spelling variations:
"padiatrische gastroenterologie" » "pediatric gastroenterology"
"klinische gastroenterologie" » "chirurgische gastroenterologie", "clinical gastroenterology", "kindern gastroenterologie"

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: "((\"klinische gastroenterologie\") OR (\"padiatrische gastroenterologie\"))".
• Removing quotes may allow a broader search: (( klinische gastroenterologie ) OR ( padiatrische gastroenterologie )).
• Adding a wildcard symbol may retrieve word variants: (("klinische gastroenterologie") OR ("padiatrische gastroenterologie"))*.