Complex sentence: Beside tuak, the Ibans also make a stronger alcoholic drink called "langkau" which is equivalent to vodka whereby a fermented tuak is heated up with fire to vaporize the alcohol which is then cooled with water and collected in a container.
Split into simpler sentences: Beside tuak, the Ibans also make a stronger alcoholic drink called "langkau". This drink is similar to vodka and brewed by heating fermented tuak with fire to vaporize the alcohol, then cooling the alcohol with water and collecting it in a container.