Question Using en vs les

Question

Lesson: I don’t find them anywhere. I wrote Je n’en trouve nulle part, which I’m told is an acceptable answer. Why is it wrong? Thanks.

Cécile Janty-Davies · Accepted Answer

Hi Liz,
There is a difference between -
Des masques? Je n'en trouve nulle part  = Masks? I can't find any, anywhere
Les masques que j'ai achetés ----> Je ne les trouve nulle part = I can't find them anywhere ( the masks I bought) 
Hope this helps!

Liz Healy · Answer

Thanks, however without more context, en could be correct. Another question in this same lesson accepted en to mean them: il s’en occupe tout de suite: he takes care of it right away or he takes care of them right away. Thanks for your help.

Cécile Janty-Davies · Answer

Hi Liz, 
In the case of your second example -
il s'en occupe tout de suite 
it is because the verb is s'occuper de quelque chose.
The following Kwiziq lesson on the use of 'en' to replace de + phrase will shed more light on the matter :
https://french.kwiziq.com/revision/grammar/the-adverbial-pronoun-en-can-replace-a-phrase-introduced-by-de