Where can I buy folding chess board ? Need help please

So something like this?
https://www.chesshouse.com/products/16-folding-tournament-chess-set-german-design-ebonized
That one doesn't have extra queens, but sounds like maybe what you're looking for.

Rochester Chess Center has one with 2" squares. A little bigger than what you are looking for but maybe it will work for you.

Folks on the forum have said good things about the sets from House Of Chess, too. I cannot vouch for them myself, but perhaps worth checking out:
http://www.houseofchess.com/wooden-chess-boards-folding.html

#5
Square size bigger is fine, but board size must not be bigger then 40×40 cm , I couldn't find a board that you recommended

Still looking
is this the style you're looking for?
https://www.hayneedle.com/product/foldinginlaidsheeshamandboxwoodchessset.cfm
Only thing missing is the notation but it fits your 40 cm overall limit. Don't know a thing about hayneedle but you can research them if this interests you.

House of Staunton has folding wooden boards, and I can't say if they have something that fits your needs but check them out.

Try an online image search. A lot of the images will have a link to another site that you can buy from. The image search will give you a nice variety of board styles and chess companies.

I need :
1.Folding chess board
2. Size 40×40 cm board, 4.5 cm square size
3. With notation
4. Velvet inside the board or something soft, not just naked wood (so the pieces don't bang agaisnt each other).
Any suggestions where to buy ?
Looks like you want a folding board and want to keep the pieces inside.
http://www.houseofchess.com/chess-boards.html
They may not ship to Russia, not sure. They sell chess equipment out of New York and will custom make stuff to order. Or at least have in the past for me, it has been several years since I purchased anything from them, so they may have changed a little. If anything, its a place to start.
I need :
1.Folding chess board
2. Size 40×40 cm board, 4.5 cm square size
3. With notation
4. Velvet inside the board or something soft, not just naked wood (so the pieces don't bang agaisnt each other).
Any suggestions where to buy ?