浪迹萍踪: drift [wander] about without any definite trace like running water or duckweed
萍踪浪迹: be a restless fellow like a drifting water plant; come and go without trace; floating about free as duckweed; have no fixed abode because of constant traveling
萍踪无定: one's whereabouts are [is] uncertain [unknown].; go hither and thither like a floating weed; roaming about; wandering aimlessly