No, the schema name is fixed. It is generated automatically by the hanacloud account cockpit and I can not change it. Just the password is chanching each time I open the tunnel. In the system view of hana studio, I'm able to see the table test but I'm not able to see the object of my package. It is just written "contains hidden objects". 
In the repository view, I'm able to see all my objects
just the test.hdbtid file refused to be activated with the error "
ERROR s0009333833trial/myhana/useraudit/db/table/test.hdbtid
Repository: Activation failed for at least one objectObject {tenant: , package: s0009333833trial.myhana.useraudit.db.table, name: test, suffix: hdbtid} has no valid references.
"
How could I check if my issue is due to missing authorization ?
Could it be that the "table import" service is not activated in my hana cloud trial platfom ?