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