While it is not really possible to confirm the sexes of your fish in these pics, it does not look like you have a female filled with eggs in them which may be your first problem. The female should be well rounded in her abdomen when she is ready to spawn. Also, if you have the fish alone and in a tank with little water movement and some live plants (for the male to anchor the bubble nest to) and there is no bubble nest, you can safely assume that either the fish are not old enough yet to breed or the water conditions are not right for spawning.
Despite what LD123 said, I've known most Gouramis to be easy to breed when given the right circumstances. In fact, the first time I saw them being bred at a fish farm, they were being bred in open bags in styrofoam boxes that where piled one on top of the other. I'd suggest you confirm gender, then age, then water conditions.