China Visa For Non Permanent Hong Kong Resident with Bangladeshi Passport

Hey Guys I'm A Bangladeshi Pesport Holder But Also have Hong Kong Non Permanent Residence ID Card, I went to Chinese Embassy in Hong Kong to Apply For L Visa with My Passport,HKID, Bank Statement but They asked me for further Documents...like 1) Guarantee Letter 2)Return Ticket 3) Hotel Booking Even My Wife Is Hong Kong Permanent Citizen....Please Advise Me how Can I get Guarantee letter if I don't Have Anyone in China.