Those who really interested in the Russian language and culture, of course, should watch the soviet films, that without doubts we can call “the gold of the Russian cinematography”. Many Russians of all generations occasionally could use phrases from those films, which are the most appropriate in the conversation. Sometimes for foreigners it would be difficult to understand the meaning of such phrases. So there are several useful expressions that are used the most.
This last quote may be difficult to understand without any context. Basically, Semyon Semyonych is actually the name of the simpleton hero in the film. We use this line to mildly reproach (in a very friendly and inoffensive way) when someone is doing or saying something evidently naïve or stupid.
All in all, watching the soviet films is very helpful when it comes to learn Russian language. They are full of interesting and authentic phrases as well as brilliant humor so one could delve into the Russian culture.