They are the primary two publications with the "Moderný Pračlovek" series (Contemporary Caveman). The main thought was to represent caveman drawings in a very very simple way and products that ended up applied at that time... and also inside our times. The first one — “Kuchyňa Pračloveka” (Caveman's Kitchen) — https://maplepublishers.com/blog/ways-to-help-you-improve-your-writing/