Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cac » van hac, van cau, van bac
cuu tre » cua tre, cau tren, cau treo
bac va » ban va, bac ha, bao va
vi cuu » vi luu, vinh cuu

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 cao)) hoi. hieu van cac ((bac va) or (thuc vat)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (nang cao)) hoi. hieu van cac ((bac va) OR (thuc vat)) hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) or (nang cao)) hoi. hieu van cac ((bac va) or (thuc vat)) hanh vi cuu tre*.