Perhaps you should try some spelling variations:
"de international seminarie prize" » "de internationaal seminarie prize" (Expand Search), "de international seminar prize" (Expand Search), "de international solidarity prize" (Expand Search), "_ international seminarie prize" (Expand Search), "het internationaal seminarie prize" (Expand Search), "en internationale seminarie prize" (Expand Search)
"de internationale samenwerking prize" » "_ international samenwerking prize" (Expand Search), "_ internationale samenwerking prize" (Expand Search), "het internationaale samenwerking prize" (Expand Search), "en internationalee samenwerking prize" (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: (("de internationale samenwerking prize") OR ("de international seminarie prize"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"de internationale samenwerking prize\") OR (\"de international seminarie prize\"))*".
• Removing quotes may allow a broader search: (( de internationale samenwerking prize ) OR ( de international seminarie prize ))*.