If you're not on the same device where you added the tags and notes, your changes likely just haven't synced. See Changes Not Syncing.
Beyond that, what exactly do you mean by "tagged and noted"? Are you referring to Zotero items, and you've added tags and child notes to the items, or are you referring to PDFs, and you're referring to PDF annotations?
Thanks for the quick response. I used Zotero desktop 6.0.7 and added tags and child notes to each PDFs. I can still see the tags on the left pane, but when searching a specific tag, no article (previously added) can be found. Also, the child notes are not there. Thanks.
Annotations tags don't yet show up anywhere other than in the annotations sidebar. They'll be viewable/searchable in the library view in a future version.
"Child notes" means something very specific — the yellow notes that appear below the top-level items in the items list. It sounds like you're probably referring to PDF annotations, which appear in the PDF viewer, though you can add them to notes.
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If you're not on the same device where you added the tags and notes, your changes likely just haven't synced. See Changes Not Syncing.
Beyond that, what exactly do you mean by "tagged and noted"? Are you referring to Zotero items, and you've added tags and child notes to the items, or are you referring to PDFs, and you're referring to PDF annotations?
"Child notes" means something very specific — the yellow notes that appear below the top-level items in the items list. It sounds like you're probably referring to PDF annotations, which appear in the PDF viewer, though you can add them to notes.