Perhaps you should try some spelling variations:
economica mexicana » economico mexicano, economica mexico, tecnologica mexicana
coleccion practica » coleccion didactica
economia mexicana » economica mexico, economia espana, academia mexicana
la cirugia » en cirugia, de cirugia
de y » de _, de a, fe y
de 3 » de _, de a

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 y) OR (de 3)) ((economica mexicana) OR (economia mexicana)) la cirugia.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "coleccion practica ((de y) OR (de 3)) ((economica mexicana) or (economia mexicana)) la cirugia.~".
• Adding a wildcard symbol may retrieve word variants: coleccion practica ((de y) OR (de 3)) ((economica mexicana) or (economia mexicana)) la cirugia.*.