Perhaps you should try some spelling variations:
van cham » van chat, van tham, va cham
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
su sach » so sach, vu sach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
luu tre » luu tru, cuu tre, luy tre
bac va » ban va, bac ha, bao va
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: su sach ky ((nang xa) or (nang ma)) hoi. hieu van cham ((bac va) or (tuc va)) hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (nang ma)) hoi. hieu van cham ((bac va) OR (tuc va)) hanh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) or (nang ma)) hoi. hieu van cham ((bac va) or (tuc va)) hanh vi luu tre*.