I'd like to request additional information.
我想要申请附加信息。
I'd like to request additional information on the report. Please find the list of the documents I need in the attached file.
我想要申请该报告的附加信息。请查看我在附件中列出的所需文件列表。

The original document should be submitted by mail.
请将原件邮寄过来。
We do require having the original document on file. Please send the original document ASAP to the address given below.
我们需要原始文件存档。请尽快将原件邮寄至以下地址。