Perhaps you should try some spelling variations:
"modified objective optimization algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithms"
"modified changing estimation algorithm" » "modified channel estimation algorithm", "modified charging station algorithm", "modified caging estimation 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 changing estimation algorithm") OR ("modified objective optimization algorithm"))~.
• Removing quotes may allow a broader search: (( modified changing estimation algorithm ) or ( modified objective optimization algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified changing estimation algorithm") or ("modified objective optimization algorithm"))*.