Hi Izabel, I'm not a teacher so I can't help you properly. But I have a downloaded podcast from BBC which explains it. It's a small 6 min "class" with a foreign studen. I can send it to you by email if you want.
Such predeterminer, determiner
used before a noun or noun phrase to add emphasis
It was such a surprise.
predeterminer, determiner, pronoun
of a particular or similar type:
A company such as ours is known for its good treatment of its staff
noun as such = in the true or exact meaning of the word or phrase:
There is no secretary as such, just a typist and receptionist.
So • adverb
1 to such a great extent. 2 extremely; very much.
3 to the same extent: he isn’t so bad as you’d think 4 referring back to something previously mentioned.
6 in the way described or demonstrated; thus.
• conjunction 1 and for this reason; therefore.
2 (so that) with the result or aim that. 3 and then. 4 introducing a question or concluding statement. 5 in the same way; correspondingly.