Perhaps you should try some spelling variations:
quan doanh » quan doan, nhuan doanh, quan hoang
doanh khoa » toan khoa
manh khai » minh khai, manh hai, dang khai
sinh khoa » sinh hoc, sinh hoat, anh khoa
sach tri » sach tai, sach tren, sach truc
tri quan » trinh quan, hai quan, mai quan
khoa hai » khoa hoi, khoa tai, khoa bai
khai hai » hai hai, khai thac, khai hoan
hai sinh » phai sinh, thai sinh, tai sinh
khoa han » khoa than, hoa han, khoa can
tu sach » thu sach, su sach, te sach
so manh » ho manh, so sanh, so danh
tong » cong, dong, song

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu sach tri quan doanh khoa hai phong ) or ( so manh khai hai sinh khoa han tong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tri quan doanh khoa hai phong ) OR ( so manh khai hai sinh khoa han tong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tri quan doanh khoa hai phong ) or ( so manh khai hai sinh khoa han tong ))*.