Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm", "modified multiobjective approximation algorithms"
"modified network optimization algorithms" » "modified network optimisation algorithm", "modified network estimation algorithm", "modified network optimized algorithms", "certified network optimization algorithms", "defined network optimization algorithms", "modified near optimization algorithms"

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