Connect two Business Object (BUS2038 and BUS0010) in Workflow!

Hi experts!

I have a Workflow based in BUS2038 (Maintenance Notification), I can see attributes like Functional Location (code).

My problem is, i can´t put Functional Location (Description) that is an attribute in BUS0010 (Functional Location) with an input Functional Location (code).

BUS2038

Input: Notification number

Output: Functional Location (code) (attribute)

BUS0010

Input: Functional Location (code)

Output: Functional Location (description) (attribute)

I want put Functional Location (description) in a mail step.

How I can achieve this?

Thank in advance