Sense Life Spell:
Syntax: cast 'sense life' <target>                      (Cleric Level 12 Spell)

By heightening the target's senses, this spell enables them to detect hidden
creatures. If no target is specified, it targets the caster.  (Min Mana = 10)

Note that Half Orcs already possess such heightened senses that, for them,
this spells offers no further bonuses.

See Also: Detect Invisibility (very low level mage spell)
          Detect Magic        (very low level mage and cleric spell)
          Detect Alignment    (very low level cleric spell)
          Detect Poison       (very low level cleric spell)
          Search              (low level thief skill to find hidden doors)