The only advice I could give you, is to continue doing cardio, lifting weights, and eating healthy.
It's impossible to figure out were your gonna lose weight next. If you think training your lower abs will help you loss weight in that specific spot, well think again, it will only strengthen them.
And by the way (I'm not trying to bring your hopes down but) losing weight that's located in and around the midsection, is the hardest weight to lose.