很 is NOT similar to 真.
很 is used before adj or adv to form a compounded adj or adv phrase, 很 is at the phrase level (inner level). But 真 modifies the whole predicate (ourter level).
We can say:
中国的风景不错。
中国的风景很不错。 很 modifies 不错.
中国的风景真(的)不错. 真 modifies the whole predicate (不错).
中国的风景真(的)很不错. 真 modifies the whole predicate (很不错).
But we can't say:
(NO)中国的风景很真不错. It is wrong because 真 can't be used at the inner level.
We can say:
中国的风景不错。
中国的风景都不错。 都 modifies 不错. inner level.
中国的风景真(的)都不错. 真 modifies the whole predicate (都不错).
But we can't say:
(NO)中国的风景都真不错. It is wrong because 真 can't be used at the inner level.
Please Note: sometimes 真 is also used at the inner level.
他跳得真高. 真 modifies 高.
他真跳得高. 真 modifies the whole predicate (跳得高).
他跳得很高. 很 modifies 高.
他真跳得很高. 真 modifies the whole predicate (跳得很高).
I guess, when only 真 appears, it can be at inner level or outer level. But if there are 2 or more modifiers, then 真 should be at outer level.
Another way to explain this:
很, 都 and 真 work in different aspects.
很 describes to "what extent" the following adj or adv imply. 很 corresponds to "very", or "very much".
都 describes the scope the following adj or adv imply. 都 corresponds to "both", or "all".
真 emphasizes the following adj or adv. 都 corresponds to "really".
So the order of them is: 真, 都, 很.
中国的风景不错.
中国的风景很不错.
中国的风景都不错.
中国的风景都很不错.
中国的风景真不错.
中国的风景真很不错.
中国的风景真都不错.
中国的风景真都很不错.