Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective estimation algorithm"
"boiler using search algorithm" » "boiler using source algorithm", "powder using search algorithm", "boiler using egarch algorithm", "boiler nursing research algorithm", "boiler using servo algorithm"

Try widening your search to All Fields.

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