Perhaps you should try some spelling variations:
"process control estadistico datos." » "process control estadisticas datos.", "process control estadistico factor.", "process control estadistica casos.", "procesos control estadistico datos.", "procesal control estadistico datos."
"proceso control statistical methods." » "proceso contra statistical methods.", "proceso contralos statistical methods.", "proces contre statistical methods.", "proceso control statistics methods.", "proceso control estadisticas methods."

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

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