Difference between QA10 / QA16

Dear QM Gurus ：

When I want to do mass UD use T-code QA10 (inspection type is 04) , no entries found . But I use QA16 to do this , I can find IL .

Of course ,before I do these , I've made sure that :

1 .RR be done and no failed RR ;

2.Production Order status is TECO ;

3. No defect existed;

4. QM view I have choose the option "auto UD ".

Can any one help to tell me why use QA10 , I can't find the IL?

So ,I want to know how difference between the QA10/QA16 ? thanks a lot !