Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective estimation algorithm"
"machines using pre algorithm" » "machinery using pre algorithm", "machines using mppt algorithm", "machines using qspr algorithm", "machines using _ algorithm", "machines nursing pre algorithm", "machines using one algorithm", "machines using ph algorithm"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("machines using pre algorithm") or ("modified multiobjective optimization algorithms"))~.
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