Perhaps you should try some spelling variations:
"methode van bavel / gtt" » "methode von bavel / gtt", "methode v bavel / gtt", "methode vom bavel / gtt"
"methode vii bavel / gtt" » "methoden vii bavel / gtt", "methods vii bavel / gtt", "method vii bavel / gtt", "methode voni bavel / gtt", "methode 1i bavel / gtt", "methode vii bases / gtt"
"methode vi bavel / gtt" » "methoden vi bavel / gtt", "methode von bavel / gtt", "methode 1 bavel / gtt", "methode vi based / gtt", "methode vi baked / gtt", "methode vi bases / gtt"
"methode 2 bavel / gtt" » "methode 2 babel / gtt"
"methode 3 bavel / gtt" » "methode 3 basel / gtt"

Try widening your search to All Fields.

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: (((((("methode van bavel / gtt") OR ((("methode vi bavel / gtt") OR ("methode 2 bavel / gtt"))))) OR ("methode vii bavel / gtt"))) OR ("methode 3 bavel / gtt")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"methode van bavel / gtt\") or (((\"methode vi bavel / gtt\") OR (\"methode 2 bavel / gtt\"))))) or (\"methode vii bavel / gtt\"))) or (\"methode 3 bavel / gtt\"))".
• Removing quotes may allow a broader search: (((((( methode van bavel / gtt ) or ((( methode vi bavel / gtt ) OR ( methode 2 bavel / gtt ))))) or ( methode vii bavel / gtt ))) or ( methode 3 bavel / gtt )).
• Adding a wildcard symbol may retrieve word variants: (((((("methode van bavel / gtt") or ((("methode vi bavel / gtt") OR ("methode 2 bavel / gtt"))))) or ("methode vii bavel / gtt"))) or ("methode 3 bavel / gtt"))*.