Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hanh vinh » thanh vinh, khanh vinh, hanh tinh
toc sach » hoc sach, doc sach, nuoc sach
vinh cuu » dinh cuu, sinh cua, dinh cu
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
lang xa » lang ha, dang xay, lang van
cuu tre » cua tre, cau tren, cau treo
xuc va » duc va, tuc va, luc va
y lang » o lang, _ lang, tay lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (thuoc sach)) y lang xa hoi. hieu van cac ((xuc va) or (thuc vat)) hanh vinh cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) y lang xa hoi. hieu van cac ((xuc va) OR (thuc vat)) hanh vinh cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) y lang xa hoi. hieu van cac ((xuc va) or (thuc vat)) hanh vinh cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) y lang xa hoi. hieu van cac ((xuc va) or (thuc vat)) hanh vinh cuu tre*.