I have a CNF statement.such as $(x_{1} \lor x_2 \lor \lnot x_3 \lor \lnot x_4) \land (x_1 \lor \lnot x_2 \lor x_3 \lor \lnot x_4) \land (x_1 \lor \lnot x_2 \lor \lnot x_3 \lor x_4) \land (x_1 \lor \lnot x_2 \lor \lnot x_3 \lor \lnot x_4) \land (\lnot x_1 \lor x_2 \lor x_3 \lor \lnot x_4) \land (\lnot x_1 \lor x_2 \lor \lnot x_3 \lor x_4) \land (\lnot x_1 \lor x_2 \lor \lnot x_3 \lor \lnot x_4) \land (\lnot x_1 \lor \lnot x_2 \lor x_3 \lor x_4) \land (\lnot x_1 \lor \lnot x_2 \lor x_3 \lor \lnot x_4) \land (\lnot x_1 \lor \lnot x_2 \lor \lnot x_3 \lor x_4) \land (\lnot x_1 \lor \lnot x_2 \lor \lnot x_3 \lor \lnot x_4)$
If I can introduce extra variables, how can I simplify it?