Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
va dinh » van dinh, va kinh, va tinh
dinh ca » dinh cac, dinh cua, dinh cao
cua tre » cua te, cuu tre, dua tren
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
va hoc » van hoc
nuoc » quoc, duoc, ngoc

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 nang ma hoi. hieu va hoc nuoc va dinh ca ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ma hoi. hieu va hoc nuoc va dinh ca ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ma hoi. hieu va hoc nuoc va dinh ca ((cua tre) or (cua triet))*.