Perhaps you should try some spelling variations:
approximation algorithm » approximation algorithms
optimisation algorithm » optimization algorithms, estimation algorithm, estimation algorithms
market optimisation » market optimization
one approximation » time approximation, _ approximation, rough approximations
modified market » modified male
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 one approximation algorithm ) OR ( modified market optimisation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (( modified one approximation algorithm ) or ( modified market optimisation algorithm ))*.