Perhaps you should try some spelling variations:
"process control estadisticas methods." » "process control estadistica methods.", "process control estadistico methods.", "process control statistical methods.", "process control estadisticas metodos.", "process control estadisticas datos.", "process control estadisticas medicas."
"procesos basados statistical methods." » "procesos base statistical methods.", "procesos basado statistical methods.", "procesos basicos statistical methods.", "procesos asociados statistical methods."

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