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 problemaasasasasasa" » "complementarity constraints problemaaasasasasasa" (Expand Search), "complementarity constraints problemasaasasasasasa" (Expand Search), "complementar constraints problemaasasasasasa" (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 problemaasasasasasa"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"complementaridade constrained problem\") OR (\"complementarity constraints problemaasasasasasa\"))".
• Removing quotes may allow a broader search: (( complementaridade constrained problem ) OR ( complementarity constraints problemaasasasasasa )).
• Adding a wildcard symbol may retrieve word variants: (("complementaridade constrained problem") OR ("complementarity constraints problemaasasasasasa"))*.