You will need to add the project field to your general ledger transaction list.
Go to General Ledger/Reports/Transactions and add the 'Project' field (you can use the short cut key ALF +F). You will now be able to see which project number the individual transactions relate to. You will also now be able to sort by project number.
Read more about editing the fields and other layouts in your Uniconta screens here:
https://www.uniconta.com/unipedia-global/layouts/