Default Adobe and OpenOffice hyphenation dictionaries contain
Code:
LEFTHYPHENMIN 3
RIGHTHYPHENMIN 3
The numbers means the minimum number of characters before and after the inserted hyphen.
Just adjust the numbers. Lower means more agressive.
There is also a slightly more complex variant available for some languages.
Code:
LEFTHYPHENMIN 2
RIGHTHYPHENMIN 3
COMPOUNDLEFTHYPHENMIN 2
COMPOUNDRIGHTHYPHENMIN 3
Use a search engine to learn what it does.