Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithm"
"modified co evolution algorithm" » "modified co solution algorithm", "modified co evolutionary algorithm", "modified co convolution algorithms", "modified _ evolution algorithm", "modified df evolution algorithm", "modified orca evolution algorithm"

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 multiobjective optimization algorithm") OR ("modified co evolution algorithm"))~.
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithm ) or ( modified co evolution algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified multiobjective optimization algorithm") or ("modified co evolution algorithm"))*.