Perhaps you should try some spelling variations:
"practica de jurisprudencia administrativa" » "practica de transparencia administrativa" (Expand Search), "practica la jurisprudencia administrativa" (Expand Search)
"Práctica y jurisprudencia comunitaria" » "Práctica y jurisprudencia tributaria" (Expand Search), "Práctica la jurisprudencia comunitaria" (Expand Search)
practica y » practica en (Expand Search), practica del (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: (("Práctica y jurisprudencia comunitaria") OR ("practica de jurisprudencia administrativa"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"Práctica y jurisprudencia comunitaria\") OR (\"practica de jurisprudencia administrativa\"))".
• Removing quotes may allow a broader search: (( Práctica y jurisprudencia comunitaria ) OR ( practica de jurisprudencia administrativa )).
• Adding a wildcard symbol may retrieve word variants: (("Práctica y jurisprudencia comunitaria") OR ("practica de jurisprudencia administrativa"))*.