These are the initial two publications to the "Moderný Pračlovek" sequence (Modern Caveman). The leading idea was to stand for caveman drawings within a quite simple way and products which were used at that time... but in addition inside our times. The very first one — “Kuchyňa Pračloveka” (Caveman's Kitchen) https://maplepublishers.com/blog/is-it-essential-to-follow-the-trend-while-writing-a-book/