How do Catholic theologians explain that there is no name for Noah's wife? She is mentioned multiple times in the book of Genesis and she kept everything in order in the ark for 12 months, so I think it is strange that she isn't named in the Bible.
Neither Roman Catholics nor just about any other Christian denominations believes that the Bible contains every detail possible. As John writes, These things are written that you might know that Jesus is the Christ.
Just about every accepted theory of inspiration suggests that the Bible that the words we have are "sufficient" (and that is the Theological(TM) term) - meaning they are enough - not exhaustive. Evangelicals are more likely to harp on things like sola scriptura than Catholics who believe in the Magesterium - but even they would reject the need for such a minor detail.
As Mark Shea, a catholic apologist writes:
In Pope Clement XI's Prayer for all things necessary for salvation, for example, supplicants pray:
The name of Noah's wife is exceedingly unlikely to inform any of these things.
An answer for the original question "How do Theologians explain that there is no name for Noah's wife."
Jewish theologians explain it this way: The identification of Na'amah, a descendant of Cain, as the wife of Noah, solves the structural flaw in Genesis as well as the above mentioned theological problem. The family of Cain is described at length in order to reveal the identity of the second mother of mankind. Her name indicates that she deserved to survive. Since mention of her family background would not have been complimentary to her, her name is not given in the present story. From her being saved it becomes clear that not all the descendants of Cain were without hope of redemption and therefore Cain received Divine Revelation.
Rabbi Naftali Tzvi Yehuda Berlin comments in his commentary Ha'amek Davar on Genesis 4: 32 "from that which was good in Cain the world was established, through this woman, and he had the privilege of joining in the survival of the world with the seed of Seth, who were the purpose of creation".
The Jewish Book of Jubilees has the following verse, which I feel answers your question:
So if you consider the teachings of around Christ's time and beforehand also inspired by the Lord (which most do) then this would be your answer.