but if I write something which doesn't violate a rule, why dismiss it if okrand never used it ? who can argue that okrand has used every possible combination in klingon, so that if what I write doesn't fall into these combinations, then it is wrong ?

There's not violating a rule, and then there's making up a new rule. You're trying to construct a sentence whose grammar doesn't follow from what we've been given, but which does mimic English grammar. This is a strong sign that you're trying to follow the rules of English to construct Klingon sentences.

If you try to make a sentence using a rule you made up, even one which doesn't seem to violate any of Okrand's rules, we're going to demand to see some justification. This is why I tell you, when you ask why can't we say *pawpu' nuq Duj what ship has arrived?, that Okrand hasn't created a rule that says nuq acts like which?, and he's never constructed a sentence that acted that way. Those are the two ways we learn the rules of Klingon: Okrand says "this is a rule," or we deduce the rules from Okrand's examples.

nuq goes in the place the answer would occupy. But if it's part of a noun-noun construction it the answer doesn't replace the entire noun-noun. If the answer were pawpu' 'entepray', what I've done is replace *nuq Duj, not just nuq, with the answer. And there's no rule that says we can do that or example of Okrand doing that.

Furthermore, Okrand has given us question words next to nouns, but they mean something very different. nuq and 'Iv work like pronouns, and you can say things like nuq Dujvetlh what is that ship? and yaSvetlh 'Iv who is that officer?

You originally asked,

we said that we can't have {'Iv} and {nuq} as part of noun-noun
constructions. but can we have the {ghorgh} and {nuqDaq} existing next
to nouns ?

for example can we say:

{ghorgh DaSjaj mamej}
when do we depart on monday ?

{DaSjaj ghorgh mamej}
on monday when do we depart

{nuqDaq tera'Daq mIl'oDmey tu'lu'}
where on earth someone finds bears ?

{tera'Daq nuqDaq mIl'oDmey tu'lu'}
on earth where someone finds bears ?

My answer is that in none of these sentences do we see question words as part of a noun-noun construction. In the first two we see an independent time expression (DaSjaj) and the question word ghorgh each standing alone. In the second two we see a locative noun (tera'Daq) and the question word nuqDaq each standing alone. There are no noun-noun constructions here.

-- 
SuStel
http://trimboli.name