Perhaps you should try some spelling variations:
"proces contreles statistical methods." » "proces control statistical methods.", "proceso contralos statistical methods.", "proces contre statistical methods.", "procesos contables statistical methods."
"process control estadisticas methods." » "process control estadistica methods.", "process control estadistico methods.", "process control statistical methods.", "process control estadisticas metodos.", "process control estadisticas datos.", "process control estadisticas medicas.", "procesos control estadisticas methods.", "proceso control estadisticas methods.", "procesal control estadisticas methods."

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("process control estadisticas methods.") OR ("proces contreles statistical methods."))~.
• Removing quotes may allow a broader search: (( process control estadisticas methods. ) or ( proces contreles statistical methods. ))~.
• Adding a wildcard symbol may retrieve word variants: (("process control estadisticas methods.") or ("proces contreles statistical methods."))*.