BT Git 28b(45) :הני מילי במילת׳ דלא שייכי אבל במילת׳ דשייכי בה עב<י>די לאחזוק׳ שיקרייהו‏ : this refers to a matter in which they are not connected, but in a matter in which they are connected, they are apt to maintain their lies
See the entire entry for šwk vb. to be connected