They are the 1st two publications for that "Contemporaryý Pračlovek" sequence (Present day Caveman). The key notion was to depict caveman drawings in the quite simple way and products which were employed at that time... and also within our times. The first a person — “Kuchyňa Pračloveka” (Caveman's Kitchen) — https://maplepublishers.com/blog/5-ways-to-self-publish-an-ebook/