Smoking pipes is a very typical image of an amiable rural old man in the 1960s in northern China, and can be seen in a lot of other stamps as well.
This stamp set is titled Advocate Quitting Smoking. Is it a little different from Anti-Smoking#65311; Actually prohibiting smoking in the public places are conducted many years later.
This one is interesting, actually I gave it to a friend for his poker collections, which seems more obvious than the title: Smoking and Health Conference. :-)