Perhaps you should try some spelling variations:
"modified multiobjective optimisation algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithm", "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective estimation algorithms"
"modified one approximation algorithms" » "modified time approximation algorithms", "modified _ approximation algorithms", "modified rough approximations algorithms", "modified male approximation algorithms", "modified near approximation algorithms", "modified orca approximation algorithms"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified one approximation algorithms") OR ("modified multiobjective optimisation algorithm"))~.
• Removing quotes may allow a broader search: (( modified one approximation algorithms ) or ( modified multiobjective optimisation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified one approximation algorithms") or ("modified multiobjective optimisation algorithm"))*.