Perhaps you should try some spelling variations:
"complementarity constraints problem" » "complementar constraints problem" (Expand Search), "complementaridade constraints problem" (Expand Search), "complementarity constraints problema" (Expand Search), "complementarity constraints problemas" (Expand Search)
"Complementarity contained problems" » "Complementarity obtained problems" (Expand Search), "Complementarity contained problemas" (Expand Search), "Complementarity contained problema" (Expand Search), "Complementarity contained problemass" (Expand Search)

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("Complementarity contained problems") OR ("complementarity constraints problem"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"Complementarity contained problems\") OR (\"complementarity constraints problem\"))".
• Removing quotes may allow a broader search: (( Complementarity contained problems ) OR ( complementarity constraints problem )).
• Adding a wildcard symbol may retrieve word variants: (("Complementarity contained problems") OR ("complementarity constraints problem"))*.