How to display short description instead of number when selecting value for a reference field?

[Mike_R · Accepted solution]

Thanks for the clarification. Unfortunately, you can only have one field as a display value.

Some workarounds that I have seen are, create a new field and have a business rule concatenate the number & short description and populate this field. Then make this field the display. 

[James Kailukai1]

I found this article 
https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0953508
I was able to both number and Short description, not sure if this works for you

The fields showing on the "Your History" tab is maintained in the Document Title table(System Classic Mobile UI -> Table Titles).

Or we can go to the "sys_ui_title.list" directly.

It can be changed following the steps below.

1. Log in as admin.

2. Go to "sys_ui_title.list".

3. Search the Table name. Create a new record if it doesn't exist.

4. Set Fields needs to be showing on the "Your History" tab.