So you come to China, maybe for pleasure, but also for work. And you want to take advantage of the lower prices, and possibly export back to your own country.
First, try to find good sources of products. Sites like Alibaba or TradeKey can help with listings.
Second, approach some manufacturers or suppliers. Often they will have someone who speaks English.
Third, visit the factory or showroom, and inspect the goods, and talk about price.
Fourth, buy and ship. The factory might be able to organise shipping.