Perhaps you should try some spelling variations:
danh dau » lanh dao, hang dau, danh tu
cua tre » cua te, cuu tre, cua triet
dau cua » dai cua, day cua, cau cua
hieu va » lieu va, hieu qua
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
vu sach » vu bach, su sach, vu khach
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cac, va cao
xac va » tac va, ac va, bac va
vu sac » vu san, va sac, vu cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sac) or (vu sach)) ky tang ma hoi. hieu va cam ((xac va) or (duc va)) danh dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sac) OR (vu sach)) ky tang ma hoi. hieu va cam ((xac va) OR (duc va)) danh dau cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu sac) or (vu sach)) ky tang ma hoi. hieu va cam ((xac va) or (duc va)) danh dau cua tre*.