Hi Swetha,
Is it true that SAP doesnt suggest / Support DS Structure enhancement ? do we have standard help documentation which i can use as a reference for my BI Team.
SAP does support data source enhancement,
If you are talking about SAP provided standard structures then answer would be yes, its not possible to enhance the SAP provided Structures.
If you are looking to enhance your data source with business required fields then you can append your own structure and Enhance with the necessary fields.
You can search in google there are lots of documents on Data source enhancements.
Your BW resource is aware of the procedure you can check with them.
If data source extract structure contains the fields but are hidden by SAP then you need to unhide those fields... not sure by unhiding the fields will be populated with values as SAP had hidden these fields might be for future releases or some fileds might get populated after unhiding them.
You can check the below link for unhiding the hidden fields by SAP.
Regards
KP