The book discusses whole board positions between fuseki and middle game. The first part (70 pages) consists of problems with typically one right and one wrong answer each. The second part discusses 50 cases on 144 pages. For each case the game's move-sequence is given and then a sort of backward problem analysis is done. I.e. a few crucial strategic decisions during the fuseki and especially its late stage are discussed using diagrams. This is like asking: "Which major problems [of decision making] did occur during the move-sequence?"
The diagrams might be understood by EU 2 kyu or stronger but preferably they are meant to be read by dan players. A lot of the diagrams contain rather simple sequences, however, it requires quite a lot of thought why just those simple ones are best. Therefore the book can be recommended especially to high dan amateurs. Lower ranked players may also read it but should invest considerably more time. ("read" means looking at the diagrams because I do not know any Korean. Anyway the text seems to be almost immaterial.)
The sequences in the explanation diagrams, the order of moves, the choice of sequences, and the impressive innovation in some of the sequences make the book worth reading. Although - as usual - I am disappointed by the typical Asian style of teaching by examples, I have to say that for the book's topic and in view of the very restricted number of diagrams the contents has about the highest quality that one could expect from traditional example books for all amateur dan players. If you do not mind the trouble of purchasing a Korean book, then you should go ahead and spend the modest USD 5 for it.