Perhaps you should try some spelling variations:
estimation algorithmssss » estimation algorithms, estimation algorithm
optimization algorithms » optimisation algorithm, estimation algorithms, estimation algorithm
location optimization » allocation optimization, static optimization
same estimation » pose estimation, sphere estimation

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: (( location optimization algorithms ) OR ( same estimation algorithmssss ))~.
• Adding a wildcard symbol may retrieve word variants: (( location optimization algorithms ) or ( same estimation algorithmssss ))*.