Yes and No
Succeeding on a Saving Throw: A creature that successfully saves against a spell that has no obvious physical effects feels a hostile force or a tingle, but cannot deduce the exact nature of the attack. Likewise, if a creature's saving throw succeeds against a targeted spell, you sense that the spell has failed. You do not sense when creatures succeed on saves against effect and area spells.
Going by this, unless they make a save, they are not aware. This is the only rules text I could find regarding awareness of spells being cast on you, other than by making psicraft/spellcraft checks when observing something be manifested.
That said, it would probably call for a Sense Motive check on their behalf if you failed to suppress the [Auditory], [Visual], and [Material] display, and if they have and make a Psicraft check to know what you're manifesting, then you probably don't even get a bluff. 'He's casting mind probe and something just tried to invade my mind' is pretty self-explanatory.
Does a caster know a charm person failed?; paizo.com/forums; rules questions
PFSRD 'Magic' chapter, subheading 'Succeeding on a Saving Throw'