When Yosef went looking for his brothers, he met a man on the road who told him "nas'u mi'zeh," they have gone away. Rashi explains that this was an angel telling Yosef that his brothers had departed from that sense of achvah, familial unity, that bound them together.
Obviously the angel gave Yosef no more than a hint, otherwise he would not have continued on to meet his brothers knowing they were plotting against him. Yet this begs the question: since Yosef did continue on his way, oblivious to the message, what was the point of telling it to him? What meaning did those words "nas'u mi'zeh" have if they did not deter Yosef from his journey?
Chazal tell us that the prophets used the expression "koh," but Moshe Rabeinu alone received prophecy that used the expression "zeh." The Maharal explains that "zeh" conveys the fact that the message is eternal. You can at any and every moment point to it -- "zeh" -- and it will be true.
The Shem m'Shmuel (VaYeishev 5677) writes that the brothers sentence against Yosef was a hora'as sha'ah, but was not strictly in accordance with the letter of the law. They felt Yosef posed a danger that had to be dealt with, whatever it took, even extra-legal means. The angel was hinting to Yosef that his brothers were abandoning "zeh" -- they were sacrificing eternal truth for the sake of expediency and the moment.
Yosef did not realize the hint at the time, but in retrospect, he understood the message. He may find himself in a pit, in an Egyptian prison, in dire circumstances, but his dreams and his vision were the "zeh" that would ultimately be realized.
The Kozhiglover writes that the expression "zos Chanukah," sharing the same root as "zeh," teaches us that the message of Chanukah does not end on the eighth day -- it continues with us long after the candles have gone out and is in fact always there.
The name Chanukah comes from the word "chinuch," training and preparation. It's very strange -- normally you prepare for something, some goal. Every Rocky movie (I haven't seen Creed, but I imagine it's true for this one too :) has the training sequence with it's music and then you have the big fight at the end. A movie with just training and no climactic ending wouldn't be as fulfilling. Yet that's Chanukah -- we are always training, always preparing. "Zos Chanukah" -- there is no end. Whatever we achieve is just preparation to go on to something bigger and better.