Hi,
Go to OLME-PO- Texts for PO - Define copying rules for item texts. Here go to info record PO text and go to text linkages. Here, you have to maintain the inforecord PO text with fixed indicator "Blank" (The texts are copied to the target document directly)
The note 448814 - FAQ: Texts in purchasing explains all the settings and control.
Regards,
AKPT