Perhaps you should try some spelling variations:
coleccion practica » coleccion didactica
practica de » practicas de
a academica » y academica, a academicos, y academicas
_ academica » _ academic, y academica, y academicas
4 cirugia » y cirugia, 8 cirugia, 9 cirugia
a cirugia » la cirugia, y cirugia, en cirugia

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

• If you are trying to use Boolean operators, they must be ALL CAPS: coleccion practica de ((a academica) OR (_ academica)) durante ((4 cirugia) OR (a cirugia)).~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "coleccion practica de ((a academica) OR (_ academica)) durante ((4 cirugia) or (a cirugia)).~".
• Adding a wildcard symbol may retrieve word variants: coleccion practica de ((a academica) OR (_ academica)) durante ((4 cirugia) or (a cirugia)).*.