As has been mentioned a lot of foods don't list certain nutrients because it isn't required by law.
Below are a couple links (same site but different nutrients) which will help you considerably: nutritiondata.self.com/foods-0001220000000
Whatever you do, do NOT take supplements for these UNLESS you have discussed it with your Dr and possibly registered Dietitian. Because we can consume a lot more of these nutrients that is recorded in our trackers, taking a supplement can cause considerable serious medical problems. Too much Potassium can cause serious heart issues, and too much Calcium can cause kidney stones, and in the supplemented form, seems to be responsible for some heart issues with some people.