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