Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithm"
"modified network estimation algorithms" » "modified network estimation algorithm", "modified network optimization algorithms", "modified network optimisation algorithm", "certified network estimation algorithms", "defined network estimation algorithms", "modified near estimation 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 network estimation algorithms") or ("modified multiobjective optimization algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified network estimation algorithms") OR ("modified multiobjective optimization algorithm")).
• Removing quotes may allow a broader search: (( modified network estimation algorithms ) or ( modified multiobjective optimization algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified network estimation algorithms") or ("modified multiobjective optimization algorithm"))*.