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."
"process control estadistica datos." » "process control estadistico datos.", "process control statistical datos.", "process economia estadistica datos.", "process control estadisticas datos.", "process control estadistica casos.", "process control estadistica usos."

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

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