Perhaps you should try some spelling variations:
ratio transformation » rate transformation, data transformation, spatial transformation
transformation a » transformation _
data transforms » data transform, data transfers, data transforming
transforms em » transforms _, transforms a, transforms b
luis debt » luis de, u.s debt
a ratio » _ ratio, a radio, e ratio
luis a » luis f, luis c
a acao » a adocao

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: (( luis debt data transforms em acao ) OR ( luis a ratio transformation a acao ))~.
• Adding a wildcard symbol may retrieve word variants: (( luis debt data transforms em acao ) or ( luis a ratio transformation a acao ))*.