Perhaps you should try some spelling variations:
"modified sphere optimization algorithms" » "modified sphere estimation algorithms", "modified sphere estimation algorithm", "modified sphere optimized algorithms", "modified stage optimization algorithms", "modified response optimization algorithms"
"modified notion optimisation algorithm" » "modified notion estimation algorithm", "modified notion estimation algorithms", "modified network optimization algorithm"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified sphere optimization algorithms") or ("modified notion optimisation algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified sphere optimization algorithms") OR ("modified notion optimisation algorithm")).
• Removing quotes may allow a broader search: (( modified sphere optimization algorithms ) or ( modified notion optimisation algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified sphere optimization algorithms") or ("modified notion optimisation algorithm"))*.