Pull only matching record from the reference field

[Vinay26]

Hi, 

I'm trying to find a solution  to below scenario:

I'm using incident table with the custom reference field. Reference field table is having 1000 records and when i tried to pass the 500 number on the incident from and click on the search for record (magnifying glass), it displays all the 1000 records list in the dialog box. But my use case is  to show only 500 record number (One record) from the entire list. Please provide the solution.

[Vinay26]

My reference table always performs the search with starts condition not the contains. 

glide.ui.ref_ac.startswith property is set to true to override this property I've created the user preference with table_name.autocomplete.contains and set to true. But no luck still performing the search with starts condition