This is the first time I ever heard of "Haw Candy".
This particular product is marketed in China as "Haw Candy" under the Heng Feng brand name.
Haw Candy is made from the Hawthorn Berry. The Boston Globe published an article about this a couple years ago, describing its taste as "cherries and apples rolled up together". Apparently, it's popular with the Chinese.
The Heng Feng version claims their product is low in sugar, and promotes the nutrients of "fresh haw", which includes 18 amino acids, vitamins, calcium, and other minerals. The candy is sweetened with honey, and is labeled as having a "sweet, sour and tasty" flavor.