Idiom for "what is apparent may not be the truth" [closed]

Solution 1:

All that glitters is not gold, and all that glistens is not gold.

• Prov. Just because something looks attractive does not mean it is genuine or valuable. (Often said as a warning.) Hollywood may look like an exciting place to live, but I don't think you should move there. All that glitters is not gold. I know Susie is popular and pretty, but don't befooled by that. All that glitters is not gold.

(McGraw-Hill Dictionary of American Idioms)

Solution 2:

there is an old saying "appearances can be deceiving"

• Things can look different from the way they really are.

e.g. Edward seems like a very nice boy, but appearances can be deceiving.

Jane may look like she doesn't understand you, but she's really extremely bright. Appearances can be deceiving.

and there is also a well known proverb: "all that glitters is not gold"

• All that glitters is not gold is a well-known saying, meaning that not everything that looks precious or true turns out to be so. This can apply to people, places, or things that promise to be more than they really are. The expression, in various forms, originated in or before the 12th century and may date back to Aesop.