Translation of table column in custom transaction

Hello experts,

I created my custom transaction by copying the standard one. The transaction view contains two tables or table views if you prefer.

Now I would like to translate one column of each table and I don't know where should I actually do this.

So far I found the program name, which is triggered after launching this transaction and I found texts in SE63 which might be translated.

The problem is I found there only some labels, buttons, titles texts but I couldn't find columns of those mentioned tables.

I would appreciate any help.
Thank you.