Perhaps you should try some spelling variations:
"het internationaale seminar prize" » "het international seminar prize" (Expand Search), "het internationaal seminarie prize" (Expand Search), "et internationale seminar prize" (Expand Search), "het interationaal seminar prize" (Expand Search), "de internationale seminar prize" (Expand Search), "_ internationale seminar prize" (Expand Search), "de internationalee seminar prize" (Expand Search)
"het internationaal de prijzen" » "_ international de prijzen" (Expand Search), "de internationale de prijzen" (Expand Search), "het international de prijzen" (Expand Search), "het internationale de prijzen" (Expand Search), "het internationale des prijzen" (Expand Search)

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: "((\"het internationaal de prijzen\") OR (\"het internationaale seminar prize\"))~".
• Removing quotes may allow a broader search: (( het internationaal de prijzen ) OR ( het internationaale seminar prize ))~.
• Adding a wildcard symbol may retrieve word variants: (("het internationaal de prijzen") OR ("het internationaale seminar prize"))*.