
Originally Posted by
nomens
You will know when she's lying or not, by looking into her eyes straight... yah straight.. don't blink.. just look straight.. if she will look at you the same way you look at her... then she's telling you the truth.. but if not.. then she's lying... then tell her...
Naay muta sa imong mata kuhaa ra gud kay minggahi na!!! 
If iya kuhaon ang muta and found out na wala diay muta... then she knows what you mean about... (LIAR)

It works most of the time but you would also need to check if she's sweating or playing/biting her nails or if she blinks as much than the usual. There are a lot of things to tell a lie but one must not only depend on the eye, some people can control it, see right through you and can turn any intimidation you're making against you. It's true, I know somebody who can.
I still don't think you need to tell the girl if she's lying. People lie to get away, some just don't want to hurt the other, others do it on purpose.