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 caging predation algorithm" » "modified caging predators algorithm", "modified caging estimation algorithm", "modified aging predation algorithm", "modified changing predation algorithm", "modified charging predation algorithm"

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