Perhaps you should try some spelling variations:
"modified objective optimization algorithm" » "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithm", "modified multiobjective optimization algorithm"
"modified passive solution algorithms" » "modified passive solution algorithm", "modified passive evolution algorithm", "modified passive convolution algorithms", "modified adaptive solution algorithms", "modified positive solutions algorithms", "modified saline solution algorithms"

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 passive solution algorithms") or ("modified objective optimization algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified passive solution algorithms") OR ("modified objective optimization algorithm")).
• Removing quotes may allow a broader search: (( modified passive solution algorithms ) or ( modified objective optimization algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified passive solution algorithms") or ("modified objective optimization algorithm"))*.