Perhaps you should try some spelling variations:
"procesos sociales statistical methods." » "procesos sociology statistical methods.", "procesos sciences statistical methods.", "procesos science statistical methods.", "proceso sociales statistical methods."
"process control estadistica methods." » "process control estadistico methods.", "process control statistical methods.", "process economia estadistica methods.", "process control estadisticas metodos.", "process control estadisticas medicas."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("procesos sociales statistical methods.") or ("process control estadistica methods."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("procesos sociales statistical methods.") OR ("process control estadistica methods.")).
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• Adding a wildcard symbol may retrieve word variants: (("procesos sociales statistical methods.") or ("process control estadistica methods."))*.