Perhaps you should try some spelling variations:
"modified invasive estimation algorithms" » "modified invasive estimation algorithm", "modified invasive optimization algorithms", "modified invasive optimisation algorithm", "modified invasive ventilation algorithms", "modified passive estimation algorithms"
"modified orca predation algorithm" » "modified orca predators algorithm", "modified orca estimation algorithm", "modified dorca predation algorithm", "modified orcad predation algorithm", "modified ohca predation algorithm"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified orca predation algorithm") or ("modified invasive estimation algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified orca predation algorithm") OR ("modified invasive estimation algorithms")).
• Removing quotes may allow a broader search: (( modified orca predation algorithm ) or ( modified invasive estimation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("modified orca predation algorithm") or ("modified invasive estimation algorithms"))*.