Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm", "modified multiobjective approximation algorithms"
"modified aging optimization algorithms" » "modified aging optimisation algorithm", "modified aging estimation algorithm", "modified aging optimized algorithms", "modified staffing optimization algorithms", "modified game optimization algorithms", "modified caging optimization algorithms"

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