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