Perhaps you should try some spelling variations:
"crítica a la solución racional formalismo" » "crítica a la solución racional formalista" (Expand Search), "crítica a la solución nacional socialismo" (Expand Search)
solucion racional » solucion racionalista (Expand Search), eleccion racional (Expand Search), accion racional (Expand Search)
la solucion » la resolucion (Expand Search), la evolucion (Expand Search), de solucion (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: crítica a la solución racional formalismo.