Why am i not getting child support help

I had kids at a very young age but it made me grow up because i had my children to think of. Now years have passed and they are almost 8 and 6 and still no financial help from there fathers. i have been a true single mother raising this kids on my own with no help from there dads. there are orders in place but no one seems to care that when a with holding notice goes threw he quits his job to avoid paying and the other does jobs under the table. what is really bs to me is my brother stopped paying for one month and they had him right up there in court in front of the judge yet my kids dads havent payed anything in years and i cant get nine into court what is wrong with this picture i need help.