Perhaps you should try some spelling variations:
"modified orca approximation algorithms" » "modified one approximation algorithms", "modified _ approximation algorithms", "modified time approximation algorithms"
"modified learning method algorithm" » "mobile learning method algorithm", "modified caging method algorithm", "modified learning mom algorithm", "modified learning methods algorithm", "modified graining methods algorithm", "modified learning emotion algorithm"

You may be able to get more results by adjusting your search query.

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