Solving cryptarithmetic problems I was recently trying to solve cryptarithmetic problems like:

       F Y H
     * E W T
     -------- 
     Z E T F
   E K Z Z
 Y Z T X
 ------------
 Y F Y W E F


But I am failing repeatedly to get the hang of such problems.I start solving problems but then I cannot get the intuition of such problems.How should I practise to master them?Any good resources in this regard?
8 4 6
    *5 7 3
  ----------
   2 5 3 8
 5 9 2 2


4 2 3 0 



4 8 4 7 5 8



where
F=8,
Y=4
H=6
E=5
W=7
T=3
Z=2
K=9
X=0
8 4 6
    *5 7 3
  ----------
   2 5 3 8
 5 9 2 2


4 2 3 0 



4 8 4 7 5 8



where
F=8,
Y=4
H=6
E=5
W=7
T=3
Z=2
K=9
X=0