"Kion ĝi havas en liaj aĉaj malgrandaj poŝoj?" would mean something like: "What does it have in his terrible little pockets?" I don't think "faras" comes into it.
To elaborate, you can sort of turn English sentences around to find out what the object is. In wh- question sentences (what, who, etc) the wh- word is often the OBJECT of the sentence, because it is what the verb happened to.
What did you eat today? I ate a ____ today. I ate a taco.
I = the thing doing the action ate = the action Taco = the victim (or "object") of the action, the thing being eaten alive
What do you have in your pocket? You have a __ in your pocket? You have a ____. You have a ring.
You = the thing doing the having have = the action taking place Ring = the prisoner being kept in the pocket
That's why kie and kien is used. Kie vi logxas - Where do you live, Kien vi iras - Where do you go to?
"Ĉu" is used to turn an ordinary statement (such as "La viro estas alta.") into a question ("Ĉu la viro estas alta?") (It's used in other ways as well, but they are not pertinent here). It's no good doing what we do in English to make a sentence into a question - changing the order of the words - because word order is much freer in Esperanto, so "Estas la viro alta" is not a question; it's just another way of saying, "La viro estas alta."
"Ĉu" is not needed here, because "Kion" is itself a question word, meaning "What". Of course, if the English was something like, "Do you have money in your pocket?" then "Ĉu" would be needed. "Ĉu vi havas monon en via poŝo?"
I'm not a specialist so I cannot help, but I think it's a little difference. Anyway if you have a sentence with"What do you have", you can say "Kion vi havas en la pošo" and it's understandable.
This is the -n ending. You'll see this in a lot of places. In this particular case it's showing you that the thing you're asking about (kion) is "receiving the action" of the verb. The verb is "havas". So, by "receiving the action" I mean that something has it. Someone else is doing the having.
That someone else here is "vi". So "vi havas" is "you have."
But when you have, you have to have something. "Vi havas ion" means "you have something".
Ion has an n on the end because it is receiving the action.
But if you want to ask, you have to say kion. Kion vi havas - what do you have?
And for those reading along, please note...
Ekspliko is a word that I barely encountered in 20 years of speaking Esperanto. Now I'm seeing it everywhere among new speakers. I wonder if it got listed in Google Translate, Tatoeba, or some other online dictionary. It's a rare word - roughly equivalent to "to explicate".
The normal word for "explanation" is klarigo.
Is "pocketses" some joke that I don't understand? Or a word from A. A. Milne's children's book, "Winnie the Pooh"? (I know that has been translated into Esperanto).