Perhaps you should try some spelling variations:
"modified objective optimization algorithmss" » "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithm", "modified multiobjective optimization algorithmss"
"defined network estimation algorithms" » "defined network estimation algorithm", "defined network optimization algorithms", "defined network optimisation algorithm", "designed network estimation 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: (("defined network estimation algorithms") OR ("modified objective optimization algorithmss"))~.
• Removing quotes may allow a broader search: (( defined network estimation algorithms ) or ( modified objective optimization algorithmss ))~.
• Adding a wildcard symbol may retrieve word variants: (("defined network estimation algorithms") or ("modified objective optimization algorithmss"))*.