This whole subject reminds me of something similar I had read about the ancient Spartans, i.e. that they felt contempt for any type of weapon which would kill from afar. So, perhaps -culturally-, this or something similar could apply for klingons as well.
On the other hand, De'vID's comment was indeed very interesting, i.e. describing an arrow with the word for spear plus the {-Hom}.
And taking this further, perhaps the ideal thing to do would be saying {thlevjaQHom} in order to describe an "arrow", since the other types of klingon spears are "hand held ones", in contrast to the {tlhevjaQ}, which is thrown with the aid of a special tool.
Or perhaps we could say also {tlhevjaQ mach}..
qunnoq