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

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("proces control estadistico methods.") OR ("proceso control statistical methods."))~.
• Removing quotes may allow a broader search: (( proces control estadistico methods. ) or ( proceso control statistical methods. ))~.
• Adding a wildcard symbol may retrieve word variants: (("proces control estadistico methods.") or ("proceso control statistical methods."))*.