Two Business Object - Send mail (Workflow Topic)

I am working with BUS2038 in a Workflow, I want to use attribute Functional Location (code) but this don´t have attributes like Functional Location (description).

This Attribute is in BUS0010 (Functional Location) then, variables input and output are:

BUS2038 (Maintenance Notification)

Input: Notification number

Output: Functional Location - code

BUS0010 (Functional Location)

Input: Functional Location - code

Output: Functional Location - Description

How are I can connect and use a mail step attribute Functional Location - Description?

Thank for your answers!!