Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified based evaluation algorithm" » "modified based evolution algorithm", "modified based estimation algorithm", "modified based solution algorithm", "modified load evaluation algorithm", "modified based gradation algorithm", "modified large evaluation algorithm", "modified male evaluation 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 based evaluation algorithm") or ("modified coverage approximation algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified based evaluation algorithm") OR ("modified coverage approximation algorithms")).
• Removing quotes may allow a broader search: (( modified based evaluation algorithm ) or ( modified coverage approximation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("modified based evaluation algorithm") or ("modified coverage approximation algorithms"))*.