Perhaps you should try some spelling variations:
estimation algorithmss » estimation algorithm, optimization algorithms
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
parameter estimation » parameter estimates, parameter optimization
policy estimation » policy optimization, pose estimation, motion estimation

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( parameter estimation algorithms ) or ( policy estimation algorithmss ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( parameter estimation algorithms ) OR ( policy estimation algorithmss )).
• Adding a wildcard symbol may retrieve word variants: (( parameter estimation algorithms ) or ( policy estimation algorithmss ))*.