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