Perhaps you should try some spelling variations:
"proceso control estadistica y." » "proceso control estadistico y.", "proceso economia estadistica y.", "proceso contra estadistica y.", "proceso contralos estadistica y.", "proces contre estadistica y.", "proceso control estadistica en.", "proceso control estadistico de.", "proceso control estadistica para."
"process control statistical methods." » "procesos control statistical methods.", "procesal control statistical methods.", "process control statistics methods.", "process control estadisticas methods."

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

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