не знает правды

doesn't know the truth

→ не
phrase Uncommon #18,161
doesn't know the truth Usually used for a third-person singular subject. The noun правды is in the genitive case; правду, the accusative form, is also possible in this expression.
RU: Он не знает правды о случившемся.
EN: He doesn't know the truth about what happened.

Она ещё не знает правды.

She doesn't know the truth yet.

Даже Том не знает правды.

Even Tom doesn't know the truth.

Том до сих пор не знает правды.

Tom still doesn't know the truth.

Том пока не знает правды.

Tom doesn't know the truth yet.

Том не знает правды.

Tom doesn't know the truth.