Perhaps you should try some spelling variations:
dieu hieu » dieu hien, dieu khien, dien chieu
hieu cac » hieu luc, hieu va, hieu van
dua tren » dung tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cac tao » cau tao, cac tro, cac tac
va dinh » van dinh, va kinh, va tinh
cuu tre » cua tre, cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang x hoi. dieu hieu cac tao va dinh van ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. dieu hieu cac tao va dinh van ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. dieu hieu cac tao va dinh van ((dua tren) or (cuu tre))*.