вот ваш код из одного предложения:
If Not [BT12:BT14].Find("a", , xlValues, xlWhole) Is Nothing Then Range(IIf([BT12] = "a", IIf([BT13] = "a", IIf([BT14] = "a", "AB12:AB14", "AB12:AB13"), IIf([BT14] = "a", "AB12,AB14", "AB12")), IIf([BT13] = "a", IIf([BT14] = "a", "AB13:AB14", "AB13"), IIf([BT14] = "a", "AB14", "")))).ClearContents
что вы можете (возможно) читать удобнее:
If Not [BT12:BT14].Find("a", , xlValues, xlWhole) Is Nothing Then Range( _
IIf([BT12] = "a", _
IIf([BT13] = "a", _
IIf([BT14] = "a", "AB12:AB14", "AB12:AB13"), _
IIf([BT14] = "a", "AB12,AB14", "AB12") _
), _
IIf([BT13] = "a", _
IIf([BT14] = "a", "AB13:AB14", "AB13"), _
IIf([BT14] = "a", "AB14", "") _
) _
) _
).ClearContents