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