That is rather different from simply adding them to the document's properties, though having done so you will find the corresponding xml code inside the docx file. As I said in your other thread ():
How you would go about that depends on whether you already have some boilerplate xml code like:

<metadata>
<SystemInfo>Customer Info</SystemInfo>
<NumberOfRecords>2</NumberOfRecords>
<FileTransferHeader>
<ProcessingDate>20150531</ProcessingDate>
<ProcessingTime>205036</ProcessingTime>
<FileName>sample.docx</FileName>
</FileTransferHeader>
</metadata>

or:

<metadata>
<SystemInfo>Customer Info</SystemInfo>
<NumberOfRecords>2</NumberOfRecords>
<FileTransferHeader>
<ProcessingDate>20150531</ProcessingDate>
<ProcessingTime>205036</ProcessingTime>
<FileName>sample.docx</FileName>
</FileTransferHeader>


<RecordsInfo>
<Name></Name>
<Address></Address>
<Author></Author>
</RecordsInfo>
</metadata>

In the first example, you'd need to add all of:

<RecordsInfo>
<Name>Rose</Name>
<Address>20150531</Address>
<Author>Admin</Author>
</RecordsInfo>

to the file, perhaps replacing </metadata> as well. In the second example, you might just want to insert:
Rose
into:
<Name></Name>
and so on - or you might want to replace the entire:

<RecordsInfo>
<Name></Name>
<Address></Address>
<Author></Author>
</RecordsInfo>
</metadata>

block with:

<Name>Rose</Name>
<Address>20150531</Address>
<Author>Admin</Author>
</RecordsInfo>
</metadata>

So, you see, it's all a matter of deciding which approach works best for you. There are no hard & fast rules about this.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]