Perhaps you should try some spelling variations:
"proceso control estadisticas methods." » "proceso control estadistica methods.", "proceso control estadistico methods.", "proceso control statistical methods.", "proceso control estadisticas metodos.", "proceso control estadisticas datos.", "process control estadisticas methods.", "proceso contra estadisticas methods.", "proceso contralos estadisticas methods."
"proceso control statistics methods." » "proceso control statistical methods.", "proceso control estadistico methods.", "proceso control estadistica methods.", "proceso control statistics methodology.", "process control statistics methods.", "proceso contra statistics methods.", "proceso contralos 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 ("proceso control estadisticas methods."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("proceso control statistics methods.") OR ("proceso control estadisticas methods.")).
• Removing quotes may allow a broader search: (( proceso control statistics methods. ) or ( proceso control estadisticas methods. )).
• Adding a wildcard symbol may retrieve word variants: (("proceso control statistics methods.") or ("proceso control estadisticas methods."))*.