Perhaps you should try some spelling variations:
approximation algorithm » approximation algorithms
optimization algorithm » optimization algorithms, optimisation algorithm, estimation algorithm
orca approximation » one approximation, _ approximation, time approximation
game optimization » stage optimization, qoe optimization, market optimization
modified game » modified male, modified adam

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• Performing a fuzzy search may retrieve terms with similar spellings: (( modified game optimization algorithm ) or ( modified orca approximation algorithm ))~.
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