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