Dog heads are generally large or medium-sized puffer fish. Common ones are Crown Dog Head, Zebra Dog Head, Mao Mao Dog Head, Red Papaya Dog Head, Kirin Dog Head, and some rare ones, such as Blue Eye Leopard Dog Head, Leopard Dog Head and Red Dot Dog Head. There is also the dream species of puffer fish lovers, the Nigerian red-spotted dog head. Of course, all the above species are freshwater puffer fish (except the golden leopard-print dog head, which is carbonized and looks like a large underwater fish). There are many sea dolphins, also known as dog heads. They really look like dogs. Perhaps the name "dog head" first came from "sea dog head".
Dolls are relatively small in size. For example, the submarine you are asking about is a golden doll, also called a green puffer fish, which belongs to soda fishing. There are also 8-character dolls and gold dolls. Other species are green dolls, which are least like puffer fish.