Perhaps you should try some spelling variations:
"procesal control estadistico methods." » "procesal control estadisticas metodos.", "process control estadistico methods.", "social control estadistico methods.", "proceso contra estadistico methods."
"procesal control statistical methods." » "process control statistical methods.", "social control statistical methods.", "proceso contra statistical methods.", "procesal control statistics methods.", "procesal control estadisticas methods."

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• Performing a fuzzy search may retrieve terms with similar spellings: (("procesal control statistical methods.") or ("procesal control estadistico methods."))~.
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