Perhaps you should try some spelling variations:
"procesos problems estadisticas methods." » "procesos problems statistical methods.", "procesos problemes d'estadistica methods.", "procesos programas estadisticos methods.", "procesos problems estadisticas metodos.", "procesos problems estadisticas datos.", "procesos penales estadisticas methods."
"procesos process statistics methods." » "procesos problems statistical methods.", "procesos process statistical methods.", "procesos process statistics methodology.", "procesos previos statistics methods."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("procesos process statistics methods.") or ("procesos problems estadisticas methods."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("procesos process statistics methods.") OR ("procesos problems estadisticas methods.")).
• Removing quotes may allow a broader search: (( procesos process statistics methods. ) or ( procesos problems estadisticas methods. )).
• Adding a wildcard symbol may retrieve word variants: (("procesos process statistics methods.") or ("procesos problems estadisticas methods."))*.