Perhaps you should try some spelling variations:
"process control estadistica con." » "process control estadistico con.", "process economia estadistica con.", "process control estadistica en.", "process control estadistica y.", "process control estadistica de."
"procesos control statistical methods." » "proceso contra statistical methods.", "procesos contables statistical methods.", "proceso contralos statistical methods.", "procesos control statistics methods.", "procesos 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: (("procesos control statistical methods.") or ("process control estadistica con."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("procesos control statistical methods.") OR ("process control estadistica con.")).
• Removing quotes may allow a broader search: (( procesos control statistical methods. ) or ( process control estadistica con. )).
• Adding a wildcard symbol may retrieve word variants: (("procesos control statistical methods.") or ("process control estadistica con."))*.