Word: how to find `_Refxxxxxxxxxx` codes for manual cross-references?

When I use the Cross Reference dialog box for cross references of figures and tables, Word creates a new field with a reference number, for example:

{REF _Ref530727267 h}

How can I get the _Refxxxxxxxxx Codes for the subtitles of my existing figures and tables? I want to insert cross-reference fields manually, because the Cross-Reference dialog box has errors and is slow.