Are you saying:
You have a single column on the table of type nvarchar
It is 28 characters long
You are given the first 14 characters
You need to return the row starting with those two characters, and the two rows before and two rows after, sorted by that column?
If so
something like
Select top 3 from table
where id > @givenId
order by id
union
select top 2 from table
where id < @givenid
order by id desc
Sorry I don't have sql server in front of me to check it out but it looks right to me!