Perhaps you should try some spelling variations:
"modified time approximation algorithm" » "modified time approximation algorithms", "modified one approximation algorithm", "modified _ approximation algorithm", "modified bi1 approximation algorithm", "modified male approximation algorithm"
"modified based gradation algorithm" » "modified based predation algorithm", "modified based estimation algorithm", "modified based evaluation algorithm", "modified based prediction algorithm", "modified male gradation algorithm"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("modified based gradation algorithm") or ("modified time approximation algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified based gradation algorithm") OR ("modified time approximation algorithm")).
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