Is there a way to extract bibliographic entries (database) from a specific document?

Is there a way to extract the bibliographic entries (created with writer and stored in document NOT as bibliography DB) and import them to Zotero?
Kind regards,

Bibliography can be included in a number of different ways. To extract such info and return it to structured form most likely requires some scripting.

Unless you have a large volume of entries and all of them are entered in the same form, manual extraction is likely to be less labor than creating, testing and devugging a script for the purpose.

Tell us some more about what you have and how the extract should be, to get better advice.

The bibliographic database is supposed to serve to allow entries in several documents to be used. Logically, then a backward query “to which document is the entry” not possible.

The approach of @keme could possibly be effective. Scripts are not my topic. Nevertheless, much success!

Well, first of all sorry for the delay. I have been experimenting and the only way i have found to do so is by exporting as Bibtex then importing in Zotero. Its not the most elegant way but at least i have saved my bibliography references. Hope this workaround will be useful to those that have not used a bibliography software from the start