essence, substance;
gist;
~ дела the gist of the matter;
дойти до ~и come* to the point;
добраться до ~и дела get* at the root of things, get* down to bedrock;
по ~и дела in reality;
as a matter of fact
essence, core, main point, gist
суть вопроса/проблемы — the crux/kernel/heart of the problem
составлять суть чего-л. — to be the essence of
по сути дела — at bottom of fact, as a matter of fact, in point of fact
дойти до сути — to come to the point, to touch the ground