Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh hai » thanh hai, nhanh hai, hang hai
ban hanh » ban hang
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
duc ban » duc tan, duc van, dua ban
hieu ve » hieu va, hieu van
tao hoi » tao khoi, tao boi, thao hoc
tay hoi » tay ho, tay thai
ky danh » ky anh, ky dang
ve cam » ve cham, ve cac, va cam
sac ky » cac ky, sai ky
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 danh ((tay hoi) OR (tao hoi)). hieu ve cam duc ban hanh hai ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky danh ((tay hoi) OR (tao hoi)). hieu ve cam duc ban hanh hai ((cua tre) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky danh ((tay hoi) OR (tao hoi)). hieu ve cam duc ban hanh hai ((cua tre) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky danh ((tay hoi) OR (tao hoi)). hieu ve cam duc ban hanh hai ((cua tre) or (cua viet))*.