Hi Leonardo.
Yes your cloud HANA Server can read the R/3 data with the help of BODS but it depends which type of deployment option you are using for the application.
As far as I know - with developer edition SAP HANA Cloud box we cannot connect the BODS. To have a more clear Idea of different types of deployment option please refer to the following link: which explains all the different types of deployment options and the difference between them.
Regards
Kumar 