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

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: (((("_ estimation algorithms") OR ("qoe estimation algorithm"))) OR ("_ optimized algorithms"))~.
• Removing quotes may allow a broader search: (((( _ estimation algorithms ) or ( qoe estimation algorithm ))) or ( _ optimized algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (((("_ estimation algorithms") or ("qoe estimation algorithm"))) or ("_ optimized algorithms"))*.