Call 1 14 for consultation first.
Second, call 160 for consultation.
Third, check online. (You can query through Baidu, industry, keywords, name, etc. )
Fourth, ask friends and acquaintances around you.
Fifth, the industrial and commercial bureau prints unit information.
Sixth, newspapers.
Seventh, radio.
In fact, there are many ways, depending on your careful discovery of various resources around you.