Perhaps you should try some spelling variations:
"progresos tecnicos artisticas methods." » "progresos tecnicas artisticas methods.", "progresos tecnica artistica methods.", "progresos tecnicas estadisticas methods.", "progreso tecnico artisticas 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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