Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithm" » "modified multiobjective optimization algorithm"
"modified over approximation algorithms" » "modified one approximation algorithms", "modified average approximation algorithms", "modified _ approximation algorithms", "modified near approximation algorithms", "modified orca approximation algorithms"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified over approximation algorithms") OR ("modified multiobjective estimation algorithm"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified over approximation algorithms\") OR (\"modified multiobjective estimation algorithm\"))".
• Removing quotes may allow a broader search: (( modified over approximation algorithms ) OR ( modified multiobjective estimation algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified over approximation algorithms") OR ("modified multiobjective estimation algorithm"))*.