I'd suggest to simply write them an email.
Be passionate about the game, tell them the problem and ask if they could help you. Maybe they can upload it for you somewhere.
I'd do it myself, but I haven't really played the game yet ^^'

What kind of content is that even? Anyway let me know if you can find it somewhere

Yes, I know a place where there are 2 seeds displayed, but your comments are closed, and Steam doesn't like links to torrents posted in the open.

Contents:
- Full OST, including unused tracks, poems, etc + translated to English tracks

- 6 trailers, 2 gameplay videos from conventions and interview

- Artworks from the game in high-quality including new art for English version

4.18 GB

That torrent was alive one week ago. Don't give up yet, maybe someone will seed it again soon. Actually, why don't you join the ice pick lodge forum and request a seed from the community?

Put this: "[Bonus] Бонусные материалы [Тургор / Tension + Тургор: Голос Цвета / The Void]"
into search engine (google or yandex). Or open comments and i'll leave direct link + magnet-link.
4 seeds currently.

The aforementioned torrent is being seeded right now.

thank you all! i did manage to get it, it just took some patience. i guess i panicked a little at the initial lack haha.

thank you for the seed

Hello - I have downloaded the bonus torrent from the discussion on Ice Pick Lodge forums, and in that thread ( https://forum.ice-pick.com/viewtopic.php?f=24&t=8915 ) there is mention of an updated torrent containing the Poems and the Hunter's prayers in German and English, alongside even more concept art and small soundtracks, and a video from Halfgild Wynac with all 3 audio tracks (ENG/GER/RUS) but I don't see any link to it. Does anyone know what became of it? I would very much like to get ahold of the English and German Poems and Prayers.