Hi  telldurges,
Refer below sample query.
SQL
DECLARE @Test AS TABLE(Bookid INT, Bookname VARCHAR(MAX), libid INT, libname VARCHAR(MAX))
INSERT INTO @Test VALUES(334,'physics',1,'LIB1')
INSERT INTO @Test VALUES(336,'math',1,'LIB1')
INSERT INTO @Test VALUES(6468,'science',1,'LIB1')
INSERT INTO @Test VALUES(357,'hindi',3,'LIB3')
INSERT INTO @Test VALUES(358,'eng',3,'LIB3')
SELECT libid, Bookid = STUFF
(
    (  
      SELECT DISTINCT ', '+ CAST(t.Bookid AS VARCHAR(MAX))  
      FROM @Test t
      WHERE t.libid = t1.libid
      FOR XMl PATH('')
    ),1,1,''  
),Libname,
Bookname = STUFF  
(  
    (  
      SELECT DISTINCT ', '+ CAST(t.Bookname AS VARCHAR(MAX))  
      FROM @Test t
      WHERE t.libid = t1.libid
      FOR XMl PATH('')
    ),1,1,''  
)  
FROM @Test t1  
GROUP BY libid ,Libname
Output
| libid | 
Bookid | 
Libname | 
Bookname | 
| 1 | 
334, 336, 6468 | 
LIB1 | 
math, physics, science | 
| 3 | 
357, 358 | 
LIB3 | 
eng, hindi |