Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified passive evolution algorithm" » "modified passive solution algorithm", "modified passive evolutionary algorithm", "modified passive convolution algorithms", "modified adaptive evolution algorithm"

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