Perhaps you should try some spelling variations:
"modified invasive optimization algorithms" » "modified invasive optimisation algorithm", "modified invasive estimation algorithms", "modified invasive estimation algorithm", "modified passive optimization algorithms"
"defined network optimization algorithms" » "defined network optimisation algorithm", "defined network estimation algorithms", "defined network estimation 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 invasive optimization algorithms") or ("defined network optimization algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified invasive optimization algorithms") OR ("defined network optimization algorithms")).
• Removing quotes may allow a broader search: (( modified invasive optimization algorithms ) or ( defined network optimization algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("modified invasive optimization algorithms") or ("defined network optimization algorithms"))*.