so we know about TEXT and possibility to add many strings to it.
But what bother me is manual said about replacing them.
As i know str_cpy dont to that and i just copy content from one string to other.
So i came to conslusion i should be able to make TEXT with 0 strings and add them as i need, but somehow i just dont know how. If im created one with TEXT itself i can change it with (text.pstring)[string_index]; But then i need to get rid of that one empty string.
Please, if any can provide good way how to make this work.

Why solutions always came after posting?
Found solution after running around engine functions and finding function txt_addstring

And even so it isnt gretest function ever.
Now it copy and add string which i passed to text through txt_addstring.
So now i just did things from other side.
Added Text string pointer to just simple used string pointer.
So now i can copy content straight into string without going through text string array.
Sorry for bothering around, but possible its usefull for someone.