/usr/share/help-langpack/vi/deja-dup/ is in language-pack-gnome-vi-base 1:16.04+20160415.
This file is owned by root:root, with mode 0o755.
..
/usr/share/help-langpack/vi/deja-dup/backup-auto.page
/usr/share/help-langpack/vi/deja-dup/backup-first.page
/usr/share/help-langpack/vi/deja-dup/contribute.page
/usr/share/help-langpack/vi/deja-dup/credits.page
/usr/share/help-langpack/vi/deja-dup/index.page
/usr/share/help-langpack/vi/deja-dup/license.page
/usr/share/help-langpack/vi/deja-dup/prefs.page
/usr/share/help-langpack/vi/deja-dup/restore-full.page
/usr/share/help-langpack/vi/deja-dup/restore-lost.page
/usr/share/help-langpack/vi/deja-dup/restore-revert.page
/usr/share/help-langpack/vi/deja-dup/restore-worst-case.page
/usr/share/help-langpack/vi/deja-dup/support.page