Besides a better fan (like a high velocity and/or blower fan) sometimes when things are heat soaked enough in small room no amount of fan/air speed will help with cooling. That’s when you introduce more fresh air to circulate the hot air out of the room. Position fans so they can pull in fresh/cooler air from another room (or window) and another to help exhaust warm air out of the room.
If that still isn’t enough then maybe look into a room AC unit to help out. Those can be had for a couple of hundred or so depending on what deals you can find. It might just be enough for those summer months.