Perhaps you should try some spelling variations:
"proceso contralos statistical methods." » "proceso control statistical methods.", "proceso contra statistical methods.", "proces contreles statistical methods.", "procesos contables statistical methods."
"proceso control estadistico methods." » "proceso control statistical methods.", "proceso control estadisticas metodos.", "process control estadistico methods.", "proceso contra estadistico methods.", "proces contre estadistico 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: (("proceso control estadistico methods.") OR ("proceso contralos statistical methods."))~.
• Removing quotes may allow a broader search: (( proceso control estadistico methods. ) or ( proceso contralos statistical methods. ))~.
• Adding a wildcard symbol may retrieve word variants: (("proceso control estadistico methods.") or ("proceso contralos statistical methods."))*.