Every game has a strategy or six. All you have to do is find someone who knows the game well and is willing to share. I’ve never heard of the game. . . . Sorry. I hope someone here will be able to help.
I don’t think there is many strategies for Sumo.
But Japan Sumo Association defines 82 different tricks. If you are able to translate the web page such as Chrome, this page might be helpful to understand. If you click the link, you will see the illustration of tricks in the next page.
If you are new to Sumo, this video is good to start.