Perhaps you should try some spelling variations:
optimisation algorithm » optimization algorithms, estimation algorithm, estimation algorithms
sphere approximation » average approximation, time approximation
game optimisation » game optimization, stage optimization, _ optimisation
one approximation » time approximation, _ approximation, rough approximations

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• Performing a fuzzy search may retrieve terms with similar spellings: (( game optimisation algorithm ) or ( ((sphere approximation) OR (one approximation)) algorithms ))~.
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