Perhaps you should try some spelling variations:
"modified optimal solution algorithms" » "modified optimal solution algorithm", "modified optimal evolution algorithm", "modified optimal convolution algorithms", "modified thermal solution algorithms"
"modified time approximation algorithms" » "modified one approximation algorithms", "modified _ approximation algorithms", "modified bi1 approximation algorithms", "modified male approximation algorithms"

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 optimal solution algorithms") OR ("modified time approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified optimal solution algorithms ) or ( modified time approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified optimal solution algorithms") or ("modified time approximation algorithms"))*.