You might be over-training if you squat and deadlift twice a week. Give your body an opportunity to heal. Try a 3 day split chest and shoulders, day off, back and biceps, day off, legs and abs, day off, then repeat the cycle over again.
Also, the fact that you calorie count can be a huge factor as well. Around the 3 year mark is where most people plateau. If you really want to get bigger and stronger after plateauing, you're going to have to have a calorie surplus. Yes, that means getting a little fatter. Do that for as long as you can handle being fat. For me it's usually about 6 months of eating whatever the fuck I want. I'll gain something like 20-30 pounds (from 175-180 to about 200 lbs), but only 5-10 pounds of that is muscle, if I'm lucky. Then go on a cutting phase to get shredded again.
Also, the fact that you calorie count can be a huge factor as well. Around the 3 year mark is where most people plateau. If you really want to get bigger and stronger after plateauing, you're going to have to have a calorie surplus. Yes, that means getting a little fatter. Do that for as long as you can handle being fat. For me it's usually about 6 months of eating whatever the fuck I want. I'll gain something like 20-30 pounds (from 175-180 to about 200 lbs), but only 5-10 pounds of that is muscle, if I'm lucky. Then go on a cutting phase to get shredded again.