Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified learning aided algorithm" » "mobile learning aided algorithm", "modified caging aided algorithm", "modified learning adam algorithm", "modified learning driven algorithm", "modified learning winner algorithm", "modified learning based algorithm", "modified learning model 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 coverage approximation algorithms") OR ("modified learning aided algorithm"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified coverage approximation algorithms\") OR (\"modified learning aided algorithm\"))*".
• Removing quotes may allow a broader search: (( modified coverage approximation algorithms ) OR ( modified learning aided algorithm ))*.