Take jeans for example; if you want to find jeans wholesaler in China, there are serveral ways to go.
1. Google search for chinese jeans wholesaler.
You will get a lot of choices from the resalt. Take some time to go through the answers, you will find some suitable wholesalers.
2. Use B2B Platform for example alibaba.com or made-in-china.com.
The are many vendors on B2B. You will find many wholesaler througn B2B.