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