百思不得骑姐
[băi sī bù dé qí jiĕ]
The literal meaning is humorous—'After A Hundred Thoughts I Couldn't Ride My Elder Sister'. This phrase could be interpreted as a whimsical way of expressing frustration over an unattainable goal or a humorous play on words, likely implying a playful sibling dynamic or inside joke rather than its literal sense.