Plaster over
Definition 1 of 2
Pro Tip 1/3Metaphorical Use
The phrase often conveys concealing true issues with temporary fixes. 
The policy changes merely plastered over deep societal issues.
Pro Tip 2/3Negative Connotation
It implies the solution is superficial and possibly deceptive. 
The company plastered over the scandal with a public apology.
Pro Tip 3/3Idiomatic Subtlety
Pay attention to context; it's not always literal, often figurative. 
The happy photos plastered over her true feelings of loneliness.