Can you check my resume? Invisible Grammar errors

I have sent some documents as my resume and follow up letter to apply for a position in a company. After an interview I was told that the documents I have sent had several grammar errors. After, I have showed my resume to more than one person, and nobody has found any errors.

I would like to ask somebody who has a deeper knowledge of English grammar, to please review my 4 pages document, and just let me know where those grammar errors are.

This, will help me, not only to think better about the answer I am giving to my (hopefully) future employer, but also to avoid to make those errors again. If somebody wants to go through this effort, I will be fully thankful.

Please just tell me how would you like me to send you my document. Regards, Sonia