Perhaps you should try some spelling variations:
"proces hoteles estadistica methods." » "proces hipotesis estadistica methods.", "proces modelos estadisticos methods.", "proces hoteles estadisticas metodos.", "proces hoteles estadisticas medicas.", "proces contreles estadistica methods."
"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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