Your fruit servings sound about right. Anecdotally, some people find themselves hungrier after a meal with fruit than after one without, it might be something to experiment with if you continue to feel hungry soon after eating, although the fruit may not have anything to do with why you're getting hungry after the salads at all.
As far as why you may feel hungry soon after a salad, there could be a couple of reasons. One, sometimes during the first few days of whole30, people just are hungrier than they expect to be, but find this evens out in a few days. Since you're only on day 2, this could be what's going on. Or, it could be that even though you are eating a large volume of food, you could use something with a little more staying power. That might mean a little more protein or fat (try the whole avocado instead of just half and see if that helps), or if you're pretty sure that's not the issue, add some more calorically dense vegetables to the salad, not just leafy greens. Add some beets (pickled or roasted), roasted potato or sweet potato chunks, carrots, jicama, fried or baked plantain. Or if you don't want to add those to your salad, do soup or a baked potato or sweet potato on the side.