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