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."
"proceso control statistics methods." » "proceso control statistical methods.", "proceso control estadistico methods.", "proceso control estadistica methods.", "proceso control statistics methodology.", "proceso contra statistics methods.", "proceso contralos statistics methods.", "proces contre statistics methods."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("proceso control statistics methods.") or ("process control estadisticas methods."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("proceso control statistics methods.") OR ("process control estadisticas methods.")).
• Removing quotes may allow a broader search: (( proceso control statistics methods. ) or ( process control estadisticas methods. )).
• Adding a wildcard symbol may retrieve word variants: (("proceso control statistics methods.") or ("process control estadisticas methods."))*.