吹灰 
吹灰 chuīhuī v.o. blow away dust
吹灰 吹灰 [chuīhuī] to blow away dust 吹灰之力 吹灰之力 [chuīhuīzhīlì] as easy as pie 
吹 吹 blow / - / mouth lack blow 灰 灰 ashes / - / cliff fire ashes 之 之 of / building block / - of 力 力 power / muscle / - power