Perhaps you should try some spelling variations:
"proceso control estadistico datos." » "proceso control estadisticas datos.", "proceso control estadistico factor.", "proceso control estadistica casos.", "process control estadistico datos.", "proceso contra estadistico datos.", "proceso contralos estadistico datos."
"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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