Perhaps you should try some spelling variations:
"modified objective optimization algorithms" » "modified objective optimisation algorithm", "modified objective estimation algorithms", "modified objective estimation algorithm", "modified multiobjective optimization algorithms"
"machines using methods algorithm" » "machinery using methods algorithm", "machines nursing methods algorithm", "machines making methods algorithm", "machines counting methods 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: (("machines using methods algorithm") OR ("modified objective optimization algorithms"))~.
• Removing quotes may allow a broader search: (( machines using methods algorithm ) or ( modified objective optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("machines using methods algorithm") or ("modified objective optimization algorithms"))*.