Perhaps you should try some spelling variations:
"problemas contextos linguistics methodology." » "problemas contextos linguisticos methodology.", "problemas contexto linguistico methodology.", "problemas contacto linguistico methodology.", "problemas concretos linguistics methodology.", "problemas candentes linguistics methodology.", "problemas internos linguistics methodology."
"process control statistics methods." » "process control statistical methods.", "process control estadistico methods.", "process control estadistica methods.", "process control statistics methodology.", "procesos control statistics methods.", "proceso control statistics methods.", "procesal control statistics 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 statistics methods.") or ("problemas contextos linguistics methodology."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("process control statistics methods.") OR ("problemas contextos linguistics methodology.")).
• Removing quotes may allow a broader search: (( process control statistics methods. ) or ( problemas contextos linguistics methodology. )).
• Adding a wildcard symbol may retrieve word variants: (("process control statistics methods.") or ("problemas contextos linguistics methodology."))*.