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