Perhaps you should try some spelling variations:
"proceso contralos statistics methods." » "proceso control statistical methods.", "proceso contralos statistical methods.", "proceso contralos statistics methodology.", "proceso contra statistics methods.", "proces contreles statistics methods.", "procesos contables statistics methods."
"process control estadisticas methods." » "process control estadistica methods.", "process control estadistico methods.", "process control statistical methods.", "process control estadisticas metodos.", "process control estadisticas datos."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("proceso contralos statistics methods.") or ("process control estadisticas methods."))~.
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• Adding a wildcard symbol may retrieve word variants: (("proceso contralos statistics methods.") or ("process control estadisticas methods."))*.