My esperanto course book taught me that ju and des can be used together to show a correlation between two statements, such as:
Ju pli mi legas ĝin, des malpli mi komprenas ĝin.
The more I read it, the less I understand.
However, sometimes I see des on its own without another phrase to show a correlation. Such as:
Ŝi eĉ ne sciis, ke okazos ekskurso, des malpli kien oni iros.
What does this mean? Why is des used for this? Is there an implied correlation to something?