Perfectly usual to miss 12 in a match if your strikers are having an off day. Over the course of a season a top striker will only score about 25% of his clear chances IRL, some days he will score 3 of 3, some days 0 of 6. That's the way it goes.
Try slowing the temp also. I usually score around 35- 50% of my shots on target in the prem. The fact your missing so many would suggest the chances your making are snap shots etc. I may not create 30 chances per game but those I do are good ones. In fact...since I just looked I think I can improve that by getting my CM to shoot less.