Unable to fetch the values from a table

[Mangesh_Mundhe]

i want to fetch the Unit Code from Unit table on the basis of unit which i have selected in the current roe which im in...I m trying using the below expression but it is not working and giving me eroors...can anyone please corre t this one and tell me whats going wrong..

Thanks in advance!

find the ss below

[TeeSee1]

Show us the table definition of the table you have this expression for (not the Unit table)