What does する mean when it does not mean "do"?
する does not actually mean "do". It's much more generic than that. "to do" is just one way it parses into English.
For your sentence あなたも血のにおいがするな. It would mean "I smell blood on you too"
する in this sense takes on the meaning "to perceive non-visually"
The kanji form of する is 為る. And the kanji 為 represents some objective. So as a verb it means "to act in a way that accomplishes [objective]" If your objective is におい then to "accomplish" it would be to smell.
This is also why ～にする means "to decide on (whatever your choice is)"
And for ～をする since を marks the direct object, it means "do ～" (Because it's a direct object, doing ～ directly accomplishes ～)
する can also be used for describing some attribute:
私は長い足をしている to mean "I have long legs"（stative resultant ている form of する)
To accomplish "long legs", the simplest way is to simply "have" it.
In this type of saying, it is almost describing a state of something. In such, it can be used somewhat loosely to describe different things.
血のにおいがする → smells like/of blood
すっぱい味がする → (has) a sour taste / "gives a sour flavour"
あの子は青い目をしている → That girl has blue eyes
友人が消防士をしている → My friend is a firefighter ("He 'does' firefighter-ing for his job")
http://japanese.about.com/library/weekly/aa060301a.htm may be this would help you いい匂いがする｡it smells good 波の音がする｡ hear the sound of the waves among others