2. Look for dealers in Fujian. As far as I know, there are many mushroom canneries in Fujian, and 80% of canned mushrooms exported from China are produced and exported here. These areas are the most concentrated areas of mushroom sales, and the throughput of mushrooms here is absolutely amazing. You have to investigate the specific situation yourself. I don't know much about the mushroom industry there. After all, it is like a mountain!
3. Look for retail dealers in various places. There are large wholesale markets for agricultural and sideline products all over the country (especially in provincial capitals). Most of the dealers here are large, and their distribution network is likely to cover the whole province. You are right to go to those places to find dealers.