tech tree question

Published on Thursday, January 25, 2024 By 9999999 In Galactic Civilizations IV

Hello, guys! I've not played GC4 sicne original release and noticed that many unique techs now are related to race abilitie. But! For example, slavery trait says that i slould have aditional slave techs, but i dont. Playing as Drengi or as a custom race. Whats is the problem? What am i missing?
And does every race has its unique technologies or not everyone?