Perhaps you should try some spelling variations:
"1000 Preguntas recurso administrativo" » "1000 Preguntas proceso administrativo" (Expand Search), "1000 Preguntas derecho administrativo" (Expand Search), "1000 Preguntas acto administrativo" (Expand Search)
"1000 Preguntas refere administrativo" » "1000 Preguntas deberes administrativos" (Expand Search), "1000 Preguntas reforma administrativa" (Expand Search), "1000 Preguntas regimen administrativo" (Expand Search)
preguntas recurso » segunda recurso (Expand Search)
preguntas refere » preguntas sobre (Expand Search)
1000 preguntas » 1.000 preguntas (Expand Search), 100 preguntas (Expand Search), 500 preguntas (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("1000 Preguntas refere administrativo") OR ("1000 Preguntas recurso administrativo"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"1000 Preguntas refere administrativo\") OR (\"1000 Preguntas recurso administrativo\"))".
• Removing quotes may allow a broader search: (( 1000 Preguntas refere administrativo ) OR ( 1000 Preguntas recurso administrativo )).
• Adding a wildcard symbol may retrieve word variants: (("1000 Preguntas refere administrativo") OR ("1000 Preguntas recurso administrativo"))*.