Due to the unfortunate necessity to 'romanize' Chinese characters names like that tend to be wrong, and once it's wrong in an RPG book every follow-on RPG will copy that same mistake (because they all canabalize each other rather than attempt original research which is usually too expensive to justify). Given that RPG stuff is very popular on the web, looking it up on a web with an incorrect name will just return a bunch of RPG sites, unfortunately. :)
The double-headed Chinese spear is normally called Shuang Tou Qiang. (Shaung is 'double', Tou is 'head', and Qiang is 'spear'. Pretty literal.) However, the double-headed spears I've seen don't really match the illustration as they don't have the crescent blade in the center. I have seen a similar crescent blade, however, on the Chinese halberd, also known as a Ji, but the crescent blade is at one end near the spear point rather than in the middle. There are double Ji's (Shaung Ji), with two crescent blades and two spear points. Put a hook on the long end of the regular Ji, and you have the original form of the Shaung Ji Gou, which eventually became the martial-arts hook sword now called Shaunggou (and likely where the Sang Kauw name got confused from). So it's not really that big of a jump to have just one crescent blade centered on the pole with spear points at either end. It's probably called something like Shaung Ji Qiang, but just as likely is called Bob, given how weapon naming works. :)