If I run the program on your data, I get:

AU: Written by: Jas  dimaano
AU: Written by: Jr  s. Tolentino, -editor
[download]

which is to be expected, as you only print something after you have modified it.

Perhaps the code you are showing us isn't the code you are actually using?

Note BTW that of the code you were showing, the second clause of the pattern in the substitution will never been matched, as anything that could potential match will be matched by the first clause.