Perhaps you should try some spelling variations:
"proces contreles statistical methods." » "proces control statistical methods.", "proceso contralos statistical methods.", "proces contre statistical methods.", "procesos contables statistical methods."
"process control estadisticas datos." » "process control estadistica datos.", "process control estadistico datos.", "process control statistical datos.", "process control estadistica casos.", "process control estadisticas metodos.", "process control estadisticas de."

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 contreles statistical methods.") OR ("process control estadisticas datos."))~.
• Removing quotes may allow a broader search: (( proces contreles statistical methods. ) or ( process control estadisticas datos. ))~.
• Adding a wildcard symbol may retrieve word variants: (("proces contreles statistical methods.") or ("process control estadisticas datos."))*.