Wisdom 2:10-24, which is the clearest prophecy about Jesus’ passion in the entire Scriptures.
Sirach 5:13-14 matches with James 1:19, Wisdom 2:12-20 with Matthew 27:41-43, and 1 Maccabees 4:36-59 and 2 Maccabees 10:1-8 with John 10:22-36.
In 2 Maccabees chapter 12, they pray for the souls of the dead. This passage is significant in that it contradicts justification by faith alone, and supports the idea of purgatory
Tobit 12:12 where the angel Raphael presents Tobit’s and Sarah’s prayers to God. This is an example of intercessory prayer instead of praying “direct to God”.
The early Church Fathers quote the deuters so many times in their writings, which also means that Tradition has had a great deal of a demand for the deuters. Read any Church Father and notice the footnotes that sow the qutoes from the Scriptures, such as Augustine who quoted the Scripture almost 43,000 times in all his writings. He makes reference to the deuters many times in order to prove a point.
I am sure if you do a search you can find a list of all the doctrines found in the deuterocanonicals. I just gave a few.