SRD:Expanded Knowledge

Expanded Knowledge [Psionic]
You learn another power.

Prerequisites
Manifester level 3rd.

Benefit
Add to your powers known one additional power of any level up to one level lower than the highest-level power you can manifest. You can choose any power, including powers from another discipline’s list or even from another class’s list.

Special
You can gain this feat multiple times. Each time, you learn one new power at any level up to one less than the highest-level power you can manifest.