Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified charging solution algorithm" » "modified charging evolution algorithm", "modified charging convolution algorithms", "modified charging evolutionary algorithm", "modified caging solution algorithm", "modified carbon solution algorithm", "modified charging station algorithm"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified coverage approximation algorithms") OR ("modified charging solution algorithm"))~.
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