Note that to continue using the same document, you'll want to replace all instances of the original citation with the new item from your library, being sure to select from the library section of the citation dialog's search results rather than the Cited section.
docx documents, you can use Reference Extractor.
If a document contains Zotero or Mendeley citations not in your library and you need to make changes to the metadata or include them in other documents, you'll need to extract the citations into your library. (This applies to the default citation dialog only, not the “classic” dialog.) Simply click Add/Edit Citation, search for an existing citation, and select it from the Cited section of the search results. Zotero can read existing citations created by the Zotero and Mendeley word processor plugins, allowing you to continue using those citations in the same document even if the items don't exist in your Zotero library.
