Perhaps you should try some spelling variations:
estimation algorithmss » estimation algorithms, estimation algorithm, optimization algorithms
optimization algorithm » optimization algorithms, optimisation algorithm, estimation algorithm
objective estimation » objective optimization, objective allocation
modified staffing » modified caging

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• Performing a fuzzy search may retrieve terms with similar spellings: (( modified objective estimation algorithmss ) or ( modified staffing optimization algorithm ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( modified objective estimation algorithmss ) OR ( modified staffing optimization algorithm )).
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