Perhaps you should try some spelling variations:
"proces muestreo statistical methods." » "proces muestreo estadistica methods.", "proces muestreo estadistico methods.", "proceso muestreo statistical methods.", "roces muestreo statistical methods.", "procesos muestreo statistical methods."
"process control estadistico methods." » "process control statistical methods.", "process control estadisticas metodos.", "procesos control estadistico methods.", "rocess control estadistico methods.", "procesoss control estadistico methods."

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