Perhaps you should try some spelling variations:
"_ optimization algorithm" » "_ optimization algorithms", "_ optimisation algorithm", "_ optimized algorithm"
"_ estimation algorithms" » "_ optimization algorithms", "_ optimisation algorithm", "_ approximation algorithms"
"risk estimation algorithm" » "pose estimation algorithm"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"risk estimation algorithm\") OR (((\"_ estimation algorithms\") OR (\"_ optimization algorithm\"))))~".
• Removing quotes may allow a broader search: (( risk estimation algorithm ) OR ((( _ estimation algorithms ) OR ( _ optimization algorithm ))))~.
• Adding a wildcard symbol may retrieve word variants: (("risk estimation algorithm") OR ((("_ estimation algorithms") OR ("_ optimization algorithm"))))*.