EntityFramework嵌套查询的五种方法

这样的双where的语句应该怎么写呢：
var test=MyList.Where(a => a.Flows.Where(b => b.CurrentUser == “”)

public class Category
{
    public int Id { get; set; }
 
    public string Name { get; set; }
 
    public virtual ICollection Posts { get; set; }
}
 
public class Post
{
    public int Id { get; set; }
 
    public string Author { get; set; }
 
    public string Title { get; set; }
 
    public int CategoryId { get; set; }
 
    public Category Category { get; set; }
}