coool. if you can i would start the beginner program even from home with your dumbells. incorporating bench press/squats/deadlifts/military press/ bent rows and such compound lifting will definately help you build a strong core and with a better diet every day and i mean a hell of a better diet eg lots of eggs, chicken, meat, fish fresh fruit and veg. try having 6 meals a day and plenty of water..10kg gain should be a pretty achievable. you really really need to up your protein intake or you wont make any significant gains. train 3 days a week and train your hardest on every single one of those days. eat eat eat!!!! get heaps of rest.
my fav quote that ive heard on this site is
"train hard, eat harder, rest hardest" live by that and you will get your 10kg
alex