How to take a bus from Taihu County, Anhui Province to Xincai County, Henan Province? thank you

Don't go to Zhumadian. This is a long detour. You go directly to Lu 'an in your north. I'm not sure if there is a through train from Lu 'an to Xincai. This is the best. If not, you can take a bus to Huangchuan County, Xinyang, where there is a direct bus to Xincai. Take the national highway 106. I looked at the map for you. This should be the shortest route to Xincai. There's another one. If you don't want to reverse, you can go west from Taihu Lake until you get off at 106 National Road, and you can go straight to Xincai. I hope it helps you.