It is strange for a non-Jew to hear that many Jews have not heard of Jewish mysticism and kabbalah simply because they were not old enough or have not completed their full training and education in Talmud and Torah. In tradition you would not have found a Jew under the age of forty plus years who have heard those words uttered. Thus is it no surprise that many other religions do not know anything about it either and that they nothing about the mystical teachings of Judaism.
Nonetheless is mystical experiences and mysticism experiences that have been part of Judaism always. When you read the Torah or learn it you hear about prophetic visions and dreams, to mystical appearances and angelic visitations. It consider as well that everybody has a soul, that there are reincarnations and wandering souls.
The Talmud however hinted at a school offered to advance religious Jews, with nothing committed to writing but it was taught only to advance Jews. Mystical thought which they love to refer to include Ezekiel’s vision with the chariot and in ancient times mystical appearances and teachings were then added to the Zohar.
As in all religions and beliefs do you get Jews who belief in mysticism while other would not as it is something that is open to personal interpretation with the traditional believers taking it very serious? When you look at Chasidic Judaism you see mysticism is an integral part of their believe and Kabbalistic reference are in the traditional prayer books of these Jews. Then you find the other side of the coin in Judaism who take it with a grain of salt while remaining faithful Jews.
An orthodox Jew recently said openly that it is Jewish nonsense and that the orthodox belief does not include mysticism. This same Judaism belief mysticism is called kabbalah which when directly translated means to receive and to accept.