Perhaps you should try some spelling variations:
de conservacion » de construccion (Expand Search)
conservacion de » construccion de (Expand Search), consolidacion de (Expand Search)
"Ley de conservación de la naturaleza de País Vasco" » "Ley de conservación de la naturaleza y País Vasco" (Expand Search)
de pais » del pais (Expand Search), de paris (Expand Search), de paix (Expand Search)

Try widening your search to All Fields.

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

• Removing quotes may allow a broader search: Ley de conservación de la naturaleza de País Vasco.