use Testdb2
go


IF NOT OBJECT_ID('[t_Demo]') IS NULL
    DROP TABLE [t_Demo]
GO
CREATE TABLE [t_Demo]
([ID] int identity(1,1) primary key not null,
[Cate] Nvarchar(20) null
)
go

INSERT [t_Demo]
SELECT '(1)' union all
SELECT '(2)' union all
SELECT '(3)' union all
SELECT '(4)' union all
SELECT '(2)' union all
SELECT '(1)' 
go

Declare @vars nvarchar(100)
set @Vars='1,2,3,5'
Declare @strSql Nvarchar(max)
set @strSql='select * from [t_Demo] where  Replace(Replace([Cate],''('',''''),'')'','''') in ('+@Vars+')'
print @strSql
exec (@strSql)

/*
select * from [t_Demo] where  Replace(Replace([Cate],'(',''),')','') in (1,2,3,5)

(5 row(s) affected)
ID    Cate
1    (1)
2    (2)
3    (3)
5    (2)
6    (1)