Where can be used to filter records same as Sql Where clause.

Sql (Where)

Select * From Table_Name
Where
Column1=some_value
and
Column2=some_another_value;

JsStore

var results = await connection.select({
    from: "Table_Name",
    where: {
        column1: some_value,
        column2: some_another_value
    }
});
//results will contains no of rows deleted.
console.log(results);

Example