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

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