Perhaps you should try some spelling variations:
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
danh du » danh dau, danh tu, dinh du
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, ma hoa, me hoi
ve cac » va cac, vien cac
xac va » tac va, ac va, bac va
du cua » duy cua, dau cua, dum cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang ((ma hoi) OR (xa hoi)). hieu ve cac ((xac va) or (duc va)) danh du cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang ((ma hoi) OR (xa hoi)). hieu ve cac ((xac va) OR (duc va)) danh du cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang ((ma hoi) OR (xa hoi)). hieu ve cac ((xac va) or (duc va)) danh du cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((ma hoi) OR (xa hoi)). hieu ve cac ((xac va) or (duc va)) danh du cua tre*.