Perhaps you should try some spelling variations:
"modified time approximation algorithm" » "modified time approximation algorithms", "modified one approximation algorithm", "modified _ approximation algorithm", "modified bi1 approximation algorithm", "modified male approximation algorithm"
"modified response optimization algorithms" » "modified response optimisation algorithm", "modified response estimation algorithms", "modified response estimation algorithm"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified time approximation algorithm\") OR (\"modified response optimization algorithms\"))~".
• Removing quotes may allow a broader search: (( modified time approximation algorithm ) OR ( modified response optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified time approximation algorithm") OR ("modified response optimization algorithms"))*.