Perhaps you should try some spelling variations:
"het eerste internationale conferentie festival" » "het eerste international conference festival" (Expand Search), "de eerste internationale conferentie festival" (Expand Search)
"en de internationale des festival" » "en _ international des festival" (Expand Search), "en de internationale doel festival" (Expand Search), "en de internationale heus festival" (Expand Search), "en de internationale het festival" (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: (("het eerste internationale conferentie festival") OR ("en de internationale des festival"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"het eerste internationale conferentie festival\") OR (\"en de internationale des festival\"))*".
• Removing quotes may allow a broader search: (( het eerste internationale conferentie festival ) OR ( en de internationale des festival ))*.