回复：谢谢8老师，不过我要是不是approval notice,

是他当初filing的文件，e.g. Perm, 140 petition copy. Does those apply to“If he/she lost the document, he/she has to ask USCIS to give him/her a duplicate"?
-No. That is different because that kind of materials belongs to your employer/sponsor, not to you (beneficial). It he/she gives it to you, that is fine. But if he/she does not give to you, that is also fine.