Perhaps you should try some spelling variations:
"proces muestreo estadistico datos." » "proces muestreo estadistica datos.", "proces estudio estadistico datos.", "proces secreto estadistico datos.", "proces muestreo estadisticas datos.", "proces muestreo estadistico factor.", "proces muestreo estadistica casos."
"process control statistical methods." » "procesos control statistical methods.", "proceso control statistical methods.", "procesal control statistical methods.", "process control statistics methods.", "process control estadisticas methods."

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