These are definitely the first two publications for that "Moderný Pračlovek" collection (Modern Caveman). The key thought was to symbolize caveman drawings in a very very simple way and products which have been utilised at that time... and also inside our days. The main one — “Kuchyňa Pračloveka” (Caveman's Kitchen https://maplepublishers.com/blog/5-ways-to-improve-your-book-self-publishing-london/