Perhaps you should try some spelling variations:
"complementarity constrained problems" » "complementar constrained problems" (Expand Search), "complementarity contained problems" (Expand Search), "complementarity constrained problemas" (Expand Search), "complementarity constrained problem" (Expand Search)
"complementaridade constraints problema" » "complementaridade constraints problemas" (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: "((\"complementarity constrained problems\") OR (\"complementaridade constraints problema\"))~".
• Removing quotes may allow a broader search: (( complementarity constrained problems ) OR ( complementaridade constraints problema ))~.
• Adding a wildcard symbol may retrieve word variants: (("complementarity constrained problems") OR ("complementaridade constraints problema"))*.