Perhaps you should try some spelling variations:
"modified df approximation algorithm" » "modified df approximation algorithms", "modified _ approximation algorithm", "modified one approximation algorithm", "modified time approximation algorithm", "modified adam approximation algorithm", "modified bi1 approximation algorithm"
"modified objective evolutionary algorithm" » "modified objective evolution algorithm", "modified objective solution 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 df approximation algorithm") OR ("modified objective evolutionary algorithm"))~.
• Removing quotes may allow a broader search: (( modified df approximation algorithm ) or ( modified objective evolutionary algorithm ))~.
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