Perhaps you should try some spelling variations:
cao quoc » cac quoc, cao thuoc, han quoc
thanh do » thanh de, thanh pho, thanh hoa
cau tren » cu tren, dau tren, ca tren
su sach » so sach, vu sach
vu khac » vu kham, vu khanh, bui khac
hieu ve » hieu va, hieu van
ve cao » va cao, ve bao, ve cac
do cau » dao cau, bo cau, co cau
x hoi » o hoi, x ho, 5 hoi
gia » giao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu khac)) ky nang ((x hoi) or (xa hoi)). hieu ve cao quoc gia thanh do cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu khac)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao quoc gia thanh do cau tren.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu khac)) ky nang ((x hoi) or (xa hoi)). hieu ve cao quoc gia thanh do cau tren*.