The sources for Jewish law have changed over the years.... I don't think any law written is the law of God anymore. The original books and teachings have been left behind. The Jewish Encyclopedia, the Judaic Encyclopedia and the Universal Jewish Encyclopedia tell us of the movement and change over time, the oldest being the Jewish Encyclopedia, and give the original outline of law and its original words. The only problem is the scribes of the Pharisees. The Jewish Encyclopedia says that the Judaism of the Old Testament and modern Judaism are very different: it says that after Nebuchadnezzar conquered Judea, 6th century BC, and led Judeans to Babylon, they had challenges to keep to their ways. Scribes of the Pharisees were put in place to write new laws. These 70 elders are mentioned to be wrong and made the law of God void. The scribes of the Pharisees prospered and there verbal Judaism was reconstructed and only written down in 135 BC; and they wrote down their religion into the Talmud which prospered and spread even to the powerful land of Khazar. Hence the two variations of the two groups: Babylon Jews and Khazar Jews; Khazar, who are mixed bloodline, making up around 70%. But the books that are read seem to be from the Old Testament, as, once they came to Europe, the scribes of the Pharisees had to adjust again. I would like to know, though: today, what do people read from? As the Jewish Encyclopedia states no one reads from the Old Testament; the 70 elders changed the course of God's word and replaced it with man made rules. What do you read: the new Babylonian Talmud or the Old Testament?
Jews read many sources.
Publicly fixed readings
We read the Torah publicly three times weekly. The entire Torah is thus read entirely each year - from "In the Beginning" until the end of Deuteronomy.
We read another section of the Bible weekly (usually something from one of the later prophets, but there's a set order). On Purim, we read the Book of Esther twice. On Tisha B'Av, we read Lamentations twice. On Passover and some before Shabbat, we read Song of Songs (Canticles). On Shavuot, we read Ruth. On Sukkot, we read Ecclesiastes.
We read many psalms in whole on a regular basis - daily, weekly, monthly - as part of our fixed prayers, or as part of various ceremonies (funerals, rememberances, etc.). Most of our prayers are also dotted with lines from or references to Psalms and Proverbs, as well as Torah and other parts of the Bible.
We also publicly read excerpts from the Talmud and from the Mishnah on a regular basis. Some congregations also read excerpts from the Zohar, a later mystical understanding of the Torah.
In other settings, Jews read many sources. Some occupy their days learning Talmud. Others read from the Bible. Others learn Zohar. Some learn midrash - stories. Others learn commentaries of the more famous rabbis or they learn laws as they've evolved over time. Many Jews who consider themselves learned can read from the Torah and Prophets directly using the Masoretic text which has remained consistent since at least the 10th century (the exact letters of the Five Books themselves have been around much longer - there have been minor changes to the later books).
Most people consider all of the above to be part of the rich corpus of Jewish thought. The Torah, the rest of the Bible, Mishnah, both Talmuds, works of law, like the Shulchan Aruch, writings of rabbis like Rashi and Ramban, the mystical Zohar, the intellectual works of moderns and the moral works like The Path of the Just. All of these are just a portion of the influences of modern Jewish thought.
Apocrypha and miscellany
As for the Khazars and the Pharisees, I think you need to read a bit more on that. It seems you have confused a number of parts of history - some of which may very well be apocryphal. I'd suggest perhaps taking a class on Jewish history if that interests you. Florence Melton Adult Mini-School is an incredible two-year program that might help you answer a lot of the questions you've been asking about Jewish thought, Jewish ethics, and Jewish history. Good luck in your quest.
The Rambam recommends spending one third of one's available time for study reading Tanach, and the other two thirds reading Talmud (Hilchot Talmud Torah 1:11).
Rabbeinu Tam on the other hand (Tosfot Sanhedrin 24a sv Belulah), feels that by reading Talmud, one also is credited with reading Tanach because the Talmud is full of citations from Tanach.