Herbal life Diet?

I have been on the herbal life diet for a while now and have only lost two kilograms. However i get hungry in between the two shakes and end up eating. The problem isnt so much that im hungry but that i crave salty food or something savoury since herbal life is relatively sweet also i sometimes have the 250ml milk but also mix in a fat free yougurt or double the milk dosage in the mixture to fill me up of i find i get hungry sooner. PLease help does anyone have any helpful suggestions for me i am 1,64m tall and weigh round 55kg id just like to lose 5 kgs. Please all suggestions are welcome.