The radical (which is usually on the left, or bottom) is sometimes semantically meaningful. In your example, 汁 has the water radical, and it is indeed a liquid. The rest of the character aside from the radical is usually entirely meaningless, aside from possibly providing the pronunciation.

As an example: 果裹猓粿蜾 are all pronounced identically - guǒ - but mean “fruit, package, monkey, rice cake, wasp” respectively. The radicals are more useful: in the last three, you have the “animal” radical (monkey), one of the “food” radicals (rice cake), and the “bug” radical (wasp).