Perhaps you should try some spelling variations:
cargas tributarias » tarifas tributarias, normas tributarias, carta tributaria
bases tributarias » base tributaria, leyes tributarias, datos tributarios
dret tributarias » dret tributari, leyes tributarias, ideas tributarias
carga tributaria » norma tributaria, materia tributaria, gaceta tributaria

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((dret tributarias) or (bases tributarias))) or (((cargas tributarias) OR (carga tributaria))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((dret tributarias) OR (bases tributarias))) OR (((cargas tributarias) OR (carga tributaria)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((dret tributarias) or (bases tributarias))) or (((cargas tributarias) OR (carga tributaria))))".
• Adding a wildcard symbol may retrieve word variants: ((((dret tributarias) or (bases tributarias))) or (((cargas tributarias) OR (carga tributaria))))*.