Perhaps you should try some spelling variations:
"procesos problems statistics methods." » "procesos problems statistical methods.", "procesos problems statistics methodology.", "procesos process statistics methods.", "procesos penales statistics methods."
"proceso control estadistico methods." » "proceso control statistical methods.", "proceso control estadisticas metodos.", "process control estadistico methods.", "proceso contra estadistico methods.", "proceso contralos estadistico methods."

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• Performing a fuzzy search may retrieve terms with similar spellings: (("procesos problems statistics methods.") or ("proceso control estadistico methods."))~.
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