[SOLVED] Why can i not get records has an array field contains primary key value in dynamoosejs?

I'm new to the dynamodb. I'm encountering an irritating problem I have a record stored in the dynamodb like this:

{
 bmgIds: ["d5a03ea2-e06e-5d01-84b7-94530b1059f7"],
 id: "d5a03ea2-e06e-5d01-84b7-94530b1059f7",
 .....
}

as you see, bmgIds array contains id value, when i used scan operation to get records has bmgIds match my condition but cannot get that record with my code

Model.scan('bmgIds').contains("d5a03ea2-e06e-5d01-84b7-94530b1059f7").exec()

I noticed that I can get records has bmgIds field not contains id value with code above

please help to explain where I'm wrong!

sorry I'm bad in English, I wish to receive help from you, thanks