The location of Xiaofang's home can be expressed as (3, 2) by several pairs; The location of the library can be represented by several pairs as (7, 6).

Xiaojun's home is in the east of Xiao Fang's home, and Xiao Fang's home is in the west of Xiaojun's home.

The library is in the northeast of Xiao Fang's home, and Xiao Fang's home is in the southwest of the library.

So the answer is: 3; 2; 7; 6; East; West; Northeast China; Southwest.