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