this morning i and my colleague ( Bangladeshi)went to Chinese emb in Hanoi for applying visa and the doxs we holding now are:invitation letter from Sister company in Qingdao,decision on business purpose letter and introduce letter which are issued from our company in Vietnam plus work permit,original passport and passport copy and Vietnam visa as well.However when we process apply they said still shortage of doxs and they listed out as following:air ticket round trip,accommodation in China,detail of schedule and itinerary in China (even though it's indicated in the invitation letter ), presenting insurances which must be translated to Chinese language (but the only this insurance i don't understand and what kind of insurance they are asking for )

Please anyone who has experienced on this issue help me to sort out what kinds of insurance should i have to prepare now?
Thanks