Wan Wun Yiu Tiet Ban Kiu
The end movements of the Biu Jee form where one bends at the waist and thrusts ones hands twords the ground.The translation is "Emergency Bend at the Waist Iron Bridges". There are several variations of this movement from lineage to lineage. In fact the most variation, as usual occurs in Yip Man Hong Kong Wing Chun.
In Kulo Village Wing Chun, this idea is inhoused in its own San Sik, actually being the 11th in the set of 12.
The core idea is the use of the Waist to bend forward, backward, Left and Right, to slip or avoid strikes, that one may have missed. It can also Add power to the strikes, when one snaps back into proper position.