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