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