paper over the cracks idiom       
 掩盖(尤指人与人之间的争执)
to hide problems, especially arguments between people, in order to make a situation seem better than it really is
  She tried to paper over the cracks, but I could see that the relationship was failing. 她试图掩盖存在的问题,但我能看出他们的关系每况愈下。