参数const val = req.body.val;const reg = new RegExp(val, 'i');Model.find({ $or: [ { key1: {$regex: reg} }, { key2: {$regex: reg} }, { key3: {$regex: reg} } ]}).sort({timestamp: -1}).exec((err, docs) => { // do something})参数const val = req.body.val;const reg = new RegExp(val, 'i');Model.find({ $or: [ { key1: {$regex: reg} }, { key2: {$regex: reg} }, { key3: {$regex: reg} } ]}).sort({timestamp: -1}).exec((err, docs) => { // do something})