It depends on what kind of truth you mean, there are subjective truths and objective truths. Divining both kinds involves different approaches.
The way I see it, by it's very nature truth was meant to exist/function in the light, so to speak.
Covering it up creates a whole plethora of other problems and situations. When it does come forward, it has the tendency to dispel the darkness (if you will) that kept it hidden.
I always know when there is more to a story, it's a slight gnawing feeling I feel in my gut or I sense when something is not being revealed in it's entirety.
I have had to rely on my instincts to divine the truth AND when I have made the concerted effort to listen to those instincts, it has never let me down.