There is no one who can interpret it: this is the same thought as expressed by the butler and the baker in 40.8.
I have heard it said of you … it: that is, “I have heard that you can interpret [explain the meaning of] a dream.” This is also expressed in some translations as “They [indefinite] say that you…” or “Some people have told me that you….”
When you hear a dream: that is, “when someone describes a dream to you” or “when you hear someone tell you what they have dreamed.”
Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .