Perhaps you should try some spelling variations:
"modified optimal optimisation algorithms" » "modified optimal optimisation algorithm", "modified optimal optimization algorithms", "modified optimal estimation algorithms", "modified thermal optimisation algorithms"
"modified objective optimization algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithm"

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 optimal optimisation algorithms") OR ("modified objective optimization algorithm"))~.
• Removing quotes may allow a broader search: (( modified optimal optimisation algorithms ) or ( modified objective optimization algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified optimal optimisation algorithms") or ("modified objective optimization algorithm"))*.