Hi @Harangad ,
Try setting the view to group with conversation view:
In the Outlook ribbon, go to the View tab, check the Show as Conversations checkbox from the Messages group. In the popping up Microsoft Outlook dialog box, click the button you need (here I click the This folder button).
The selected email chain is then arranged by conversation. You can see an attachment icon displayed on the right of the mailing list.
Click on the white triangle to expand the current conversation. You can then find the corresponding attachments in the original messages.