Is there any manuscript among the Dead Sea scrolls, which foretold something that happened after the manuscript was written?
The Dead Sea Scrolls are not themselves a unique set of content, but rather a collection --rather like someone's private library-- of various texts from the time period that were all preserved together and help us understand the state of those texts at a specific point in time.
One example would be the Isaiah scroll, a basically complete copy of the entire book of Isaiah in one place. The book of Isiah was written ~750 years before Christ and includes many specific descriptions of what is life, dead and resurrection would be like.
Isaiah 53:7-9 (ESV)
He was oppressed, and he was afflicted,
yet he opened not his mouth;
like a lamb that is led to the slaughter,
and like a sheep that before its shearers is silent,
so he opened not his mouth.
By oppression and judgment he was taken away;
and as for his generation, who considered
that he was cut off out of the land of the living,
stricken for the transgression of my people?
And they made his grave with the wicked
and with a rich man in his death,
although he had done no violence,
and there was no deceit in his mouth.
You can see these verses on the scroll here. If you are interested there are lots of commentaries available on the hundreds of specific things Isaiah foretold about the Messiah that were fulfilled in the person of Jesus.
Also be aware that other works besides canonical scriptural texts were among the scrolls found. There are other works from the time period. The find has no particular affect on what text are or are not considered scripture any more than looking at the titles in a pastor's library today would prove one way or another what he believed, but the quality and quantity of texts found together do provide collaborative evidence for the integrity of other copies of the texts that were found elsewhere and in smaller chunks.
Yes again! "They have pierced my hands and my feet." - Psalm 22v16.
Admittedly, this verse will be argued against by Jews and unbelievers until the last day, but here goes:-
The Hebrew Masoretic text was produced by Jews several hundred years after the time of Christ (and who, of course, did not accept Jesus of Nazareth as their Messiah). The (English translation of the) Masoretic Text Psalm 22 verse 16 says:- "Like a lion are my hands and my feet."
On the other hand the Jewish producers of the Septuagint, the Greek translation of the Old Testament, translated before the time of Christ by Jews in Egypt had translated it:- "They have dug my hands and my feet." The word "dug" can be understood as "dug through" or "pierced".
The Septuagint was needed because many Jews in the diaspora had Greek as their first language. Hebrew was falling/had largely fallen into disuse, not just because of Greek but also because of Aramaic.
There is a subtle difference between the Hebrew words for "like a lion" and "they have pierced" - the left most letter is different. In one it ends [Hebrew reads right to left] with the longer letter vav (ו) rather than the shorter yod (י), giving כארו ka'aru. This is not a currently recognised word in the Hebrew language, but without the aleph it becomes כרו, "dug", "mined", or "excavated".
It is true that the Hebrew word for "they have pierced", with the aleph included, is not used elsewhere in the Old Testament and it is difficult therefore to be certain of translation: but the point for me is that the translators of the Septuagint had no motive for misrepresenting the translation of the Hebrew, and in addition were very likely better at Hebrew than the Masoretic Jews, and far better at ancient Hebrew than modern Hebrew speakers and scholars who argue against their translation. What the Septuagint translators seem to be essentially saying is that the inclusion of the aleph in the Hebrew represents a variant spelling.
When the Dead Sea Scrolls became available it was naturally of major interest what the left most letter would be.
I quote from "The Dead Sea Scrolls Bible - The Oldest Known Bible Translated for the First Time into English", translated and with commentary by Martin Abegg Jr, Peter Flint & Eugene Ulrich, HarperCollins, 1999 :-
' Among the scrolls the reading in question is found only in the Psalms scroll found at Nahal Hever (abbreviated 5/6HevPs), which reads "They have pierced my hands and my feet"! '