Hello Asish Nehra,
Below options to check from front end.
1) Open vendor payment journal form and go to Options > Record info.

--- Here you will find Show all fields tab as shown above.
--- Once you click on this; you will see the records. It will also give you the exact Table description which is "Ledger journal table".

--- If you further scroll down, then you will see the Table ID.

--- Then just filter either with this Table ID or Table description in "Active document tables" form. You will be able to identify the exact table detail which need to activate to attach document in posted vendor payment journal form. Set the "Always Enabled" check box enabled for this Table ID.

2) Another option is to click on Script tab as shown in my 1st screenshot above.
Once you click on this; a ".txt" file will be generated from system.
In that file also; you can see the Table description which is "LedgerJournalTable".

Kindly check and provide your feedback.
Best regards,
Sourav Dam
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