Perhaps you should try some spelling variations:
"modified allocation optimization algorithms" » "modified allocation optimisation algorithm", "modified allocation estimation algorithms", "modified allocation estimation algorithm", "modified location optimization algorithms"
"modified robust estimation algorithmss" » "modified robust estimation algorithms", "modified robust estimation algorithm", "modified robust optimization algorithmss", "modified pose estimation algorithmss", "modified risk estimation algorithmss"

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 allocation optimization algorithms") OR ("modified robust estimation algorithmss"))~.
• Removing quotes may allow a broader search: (( modified allocation optimization algorithms ) or ( modified robust estimation algorithmss ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified allocation optimization algorithms") or ("modified robust estimation algorithmss"))*.