Everything is true, it means that it has to change at all times. Existence is nothing without changing even just seconds. Nothing seems to bring nothing interesting explorations is because it is all suffering.
That means that everything is true It has changed over time. Nothing remains without change. Although only a fraction of a second Nothing is as it seems, nothing fascinating. It too is suffering
Not everything is true, that means It is constantly changing. Nothing exists without change, even if only for a fraction of a second, it's nothing. It's nothing attractive.