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