Perhaps you should try some spelling variations:
"complementaridade constrained problem" » "complementaridade contained problem" (Expand Search), "complementaridade constrained problema" (Expand Search), "complementaridade constrained problemas" (Expand Search)
"complementarity constraints problems" » "complementarity constraints problemas" (Expand Search), "complementarity constraints problemass" (Expand Search), "complementar constraints problems" (Expand Search), "complementarity constraints problema" (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: (("complementaridade constrained problem") OR ("complementarity constraints problems"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"complementaridade constrained problem\") OR (\"complementarity constraints problems\"))".
• Removing quotes may allow a broader search: (( complementaridade constrained problem ) OR ( complementarity constraints problems )).
• Adding a wildcard symbol may retrieve word variants: (("complementaridade constrained problem") OR ("complementarity constraints problems"))*.