You need to be a bit more organised with your testing. Random testing doesn't really tell you very much.
Testing immediately before you eat then 2 hours after first bite will help you more than a few random ones. If you do this, and keep a food diary including portion sizes and everything on your plate then record your levels alongside, you can see at a glance what that food has done to your levels. You need to concentrate first on the actual rise from before eating to after. It is important to keep that rise down as far as you can. Any more than 2mmol/l and there are too many carbs in that meal, preferably less than 1.5mmol/l. You will soon see some patterns emerging on your food diary and be able to tweak some of your meals. This is called eating to your meter.