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 policy optimisation algorithm" » "modified policy optimization algorithms", "modified policy estimation algorithm", "modified policy estimation algorithms", "modified policy optimization algorithm", "modified topology optimization 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 policy optimisation algorithm\"))~".
• Removing quotes may allow a broader search: (( modified time approximation algorithm ) OR ( modified policy optimisation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified time approximation algorithm") OR ("modified policy optimisation algorithm"))*.