Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
chat tuc » chat xuc, luat tuc, chat huu
hieu van » thien van, lieu va, hieu ve
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
va dinh » van dinh, va kinh, va tinh
dinh vi » dinh ve, dinh viet, dinh tri
luu tre » luu tru, cuu tre, luy tre
tuc va » thuc va, truc va, tuc xa
vi luu » vi lua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ty ((nang xa) or (nang ma)) hoi. ((hieu van) or (hieu va)) chat tuc va dinh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty ((nang xa) OR (nang ma)) hoi. ((hieu van) OR (hieu va)) chat tuc va dinh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: hoc sach ty ((nang xa) or (nang ma)) hoi. ((hieu van) or (hieu va)) chat tuc va dinh vi luu tre*.