冷眼旁观看你们暧昧不清
[lĕng yăn páng guān kàn nĭ men ài mèi bù qīng]
'Watching you with cold eyes being ambiguous and vague.' Conveys the idea of someone who observes others' vague and ambiguous behavior without emotion or judgment, likely hinting at indifference or objectivity towards such interactions.