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

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 lighting optimisation algorithm ) OR ( modified time approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (( modified lighting optimisation algorithm ) or ( modified time approximation algorithm ))*.