Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one 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 notion approximation algorithms") OR ("modified learning method algorithm"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified notion approximation algorithms\") OR (\"modified learning method algorithm\"))".
• Removing quotes may allow a broader search: (( modified notion approximation algorithms ) OR ( modified learning method algorithm )).
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