Apart from your traps, snatches and C&J won’t do that much for upper body hypertrophy. Your triceps and shoulders are used primarily for supporting strength - there is no real weighted pressing action in a snatch or C&J, it’s mostly leg drive and then your arms are used to drive the body under the bar, not drive the bar above the head. Your chest is doing virtually nothing. You will hit the upper back hard during the pull, but you’re only loading it for less than a second. You’re also using very low reps - singles, doubles and triples aren’t the best rep range for hypertrophy.
If you look at the beefier O lifters (guys like Klokov, Chigishev, Guozheng) they’re usually the guys from countries that do a lot of additional assistance work. If you look at the guys from the golden age of Bulgarian lifting, when they were pretty much doing just snatches, C&J and front squats, none of them have very big upper bodies.
My advice would be to do some extra stuff at the end of your sessions - hammer curls (pretty much the only curl worth doing for an O lifter), pullups/chins, dumbell rows (you need a strong upper back to really hammer those front squats), and maybe some dumbell benching if you can stay flexible enough to hit the bottom position in a snatch properly. Add some ab work like ab pulldowns and planks, and maybe some general shoulder/elbow health work like scarecrows and band pushdowns and you’re good to go. Spit it up over the course of the week.