Can I add new compounding field in 0RT_VEND ?

Due to 0RT_VENDP_TEXT datasource has 3 keys (Language key, Vendor, Vendor Sub-Range) but 0RT_VENDP has 2 keys (Language key, Vendor Sub-Range) that maybe duplicate when 2 vendor have same Vendor Sub-Range code

Sample#1

Language key, Vendor, Vendor Sub-Range, Description

EN, 100, 20, Office product

EN, 200, 20, Office product

Sample#2

Language key, Vendor, Vendor Sub-Range, Description

EN, 100, 20, Office product

EN, 200, 20, Furniture product

My Question:

1. Can I add new compounding field in 0RT_VEND ? Best Solution ?

2. Each Vendor Sub-Range Code must same description ?? I don't know about Vendor Sub-Range concept

Help me please

Thank you very much