Term is PoJo class{
 svcId;
 bnftId;
 svcDesc;
 rowNum;
}

List<Term> list = new ArrayList<>();


        for(int i=0;i<5;i++) {
            Term s = new Term();
            if(i==0) {
                s.setRowNum(1);
                s.setBnftId(101);
                s.setSvcDesc("Test1");
                s.setSvcId(20);}
            if(i==1) {
                s.setRowNum(1);
                s.setBnftId(111);
                s.setSvcDesc("Test1");
                s.setSvcId(20);}
            if(i==2) {
                s.setRowNum(2);
                s.setBnftId(121);
                s.setSvcDesc("Test3");
                s.setSvcId(30);}
            if(i==3) {
                s.setRowNum(3);
                s.setBnftId(131);
                s.setSvcDesc("Test4");
                s.setSvcId(40);}
            if(i==4) {
                s.setRowNum(3);
                s.setBnftId(141);
                s.setSvcDesc("Test4");
                s.setSvcId(40);}

            list.add(s);
        }
Map<Integer, List<Term>> collect = list.stream().collect(Collectors.groupingBy(Term::getRowNum)).entrySet().stream().filter(v-> v.getValue().size()>=2).collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
collect.entrySet().stream().findFirst().forEach( x -> System.out.println("Key : " + x.getKey() + " Value : " + x.getValue()));

(Key)RowNum is :1
(Value)rowNum=1, svcDesc=Test1, bnftId=101, svcId=20
(Value)rowNum=1, svcDesc=Test1, bnftId=111, svcId=20
(Value)rowNum=1, svcDesc=Test1, bnftId=1134, svcId=20
(Key)RowNum is :3
(Value)rowNum=3, svcDesc=Test4, bnftId=131, svcId=40
(Value)rowNum=3, svcDesc=Test4, bnftId=141, svcId=40
(Value)rowNum=3, svcDesc=Test4, bnftId=141, svcId=40
(Value)rowNum=3, svcDesc=Test4, bnftId=141, svcId=40