Perhaps you should try some spelling variations:
"modified allocation approximation algorithms" » "modified allocation optimization algorithms"
"modified charging estimation algorithms" » "modified charging estimation algorithm", "modified charging optimization algorithms", "modified charging optimisation algorithm", "modified charging station algorithms", "modified caging estimation algorithms", "modified carbon estimation algorithms"

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 charging estimation algorithms") OR ("modified allocation approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified charging estimation algorithms ) or ( modified allocation approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified charging estimation algorithms") or ("modified allocation approximation algorithms"))*.