when you use 很， there may be no personal feelings in the sentence， it's just description。 but when you use 真，its more like you are admiring the object you want to describe，or there may be some negative feelings in it。 hope this could help you。

In situations which your mentioned above, ZHEN and HEN are all used as adverbs, and they are similar in meaning. In fact, the difference between them is just the extent they express. ZHEN contains more subjective feeling, and often used in spoken language and informal communication, while HEN seems more objective, and people prefer to use it as formal one.

You can use HEN to instead of ZHEN, or vice versa. In my opinion, ZHEN is more serious than HEN. For instanse, I really like this book. I like this book very much. You might feel this in English better.

真is more stronger than很

I think have not so much different! IN English Li ru (例如）can use Such as or For example ! hen(很） or zhen （真）both use! Praise something can use hen（很）zhen（真）tai(太）te(特）and so on