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