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