Many of them say that travelling helps them to understand their own country better.

At thate same time, others people believe that an understanding of your own country doesn`'t require travelling abroad; on the contrary, it may impede toa person's ability to love and appreciate his own country.

In my opinion, comprising of two things always helps to understand better everyeach of them better.

Not sure that "comprising" is the word you are looking for here. This sentence needs to be reformulated to be understood

So, if a person goes abroad, firstly he can see differencies between his own country and another country.

For example, something the person took for granted in his own country may be absent in another country, and this fact may provoke thinking about the reasons ing behind the history and culture of his homeland.

Second, talking about foreingn cultures with habitants of foreingn countryies may make one ponder what he could tellexplain about his onwn culture.

On the contrary, travelling will distract him from the motherland.

BThis is because one must visit all regions of his country before he goinges somewhere else.

In formal/written English, we don't normally start sentences with "because", because the sentence will often be a fragment. To express the complete idea, it is better to say "this is because"

I amdo not agree with this opinion for one particular reason: nobody can learn something quite as deeply without comparison withng it to different versions.

To sum up, I would like to say that it is impossible to enrich one's knowingledge about histheir country without traveling abroad.