Perhaps you should try some spelling variations:
"proceso control statistics methods." » "proceso control statistical methods.", "proceso control statistics methodology.", "proceso control estadistico methods.", "proceso control estadistica methods.", "process control statistics methods.", "proceso contra statistics methods.", "proceso contralos statistics methods."
"social control statistics methods." » "social control statistical methods.", "social control statistics methodology.", "social control estadistico methods.", "social control estadistica methods."

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