Perhaps you should try some spelling variations:
quoc lan » nuoc luan, quoc quan, quoc danh
quoc ban » quoc bao, quoc quan, quoc binh
cua tre » cua te, cuu tre, cua triet
xanh di » danh di, vanh dai, xanh tai
hieu va » lieu va, hieu qua
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu van
ky sang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
di cua » dai cua, doi cua, de cua
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky sang ma hoi. ((hieu ve) OR (hieu va)) cham ((quoc ban) or (quoc lan)) xanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky sang ma hoi. ((hieu ve) OR (hieu va)) cham ((quoc ban) OR (quoc lan)) xanh di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky sang ma hoi. ((hieu ve) OR (hieu va)) cham ((quoc ban) or (quoc lan)) xanh di cua tre*".