chở củi về rừng,

Syms: take coals to Newcastle

to supply something to a place or person that already has a lot of that particular thing.

to do something unnecessary; bring or furnish something of which there is plenty.

Newcastle is an English city near many coal mines, and coal is sent out there to other places.

Exporting pine to Scandinavia seems like carrying coals to Newcastle. Xuất khẩu gỗ thông sang các nước vùng Scandinavia dường như là chở củi về rừng.