Perhaps you should try some spelling variations:
approximation algorithm » approximation algorithms
solutions algorithm » solution algorithm, evolution algorithm, evolutionary algorithm
modified positive » modified passive, modified adaptive
one approximation » time approximation, _ approximation, rough approximations
modified one » modified male, modified near, modified orca

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 positive solutions algorithm ) OR ( modified one approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (( modified positive solutions algorithm ) or ( modified one approximation algorithm ))*.