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