Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
dinh vai » dinh van, dinh vi, dinh va
sach ky » sach y, sach ty, sach kem
hieu va » lieu va, hieu qua
va dinh » van dinh, va kinh, va tinh
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
sac ky » cac ky, sai ky
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) OR (sac ky)) nang x hoi. ((hieu van) or (hieu va)) co hoc va dinh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. ((hieu van) OR (hieu va)) co hoc va dinh vai cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) nang x hoi. ((hieu van) or (hieu va)) co hoc va dinh vai cuu tre*".