国 can be broken down into □ and 玉.
There are two kinds of notation of 玉 and 王 in the old dictionary.
玉 is marvelous because it is the land where the king rules.
Why 玉?
There are two theories.
One is something that adds points.
The other is the one with a point attached by omitting the old font.
Write 国 as 國 in the old font.
It is a sharp abbreviation method