Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
trinh di » trinh do, trinh dien, trinh dinh
tinh di » tinh doi, tinh da, tin di
cac duc » cac du, cao duc, cac dac
hieu va » lieu va, hieu qua
sach ly » sach y, sach lo, sach ty
nang xa » lang xa, nang ma, mang xa
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ly ((nang xa) or (nang x)) hoi. hieu va cac duc va ((tinh di) OR (trinh di)) cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ly ((nang xa) OR (nang x)) hoi. hieu va cac duc va ((tinh di) OR (trinh di)) cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ly ((nang xa) or (nang x)) hoi. hieu va cac duc va ((tinh di) OR (trinh di)) cua te".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ly ((nang xa) or (nang x)) hoi. hieu va cac duc va ((tinh di) OR (trinh di)) cua te*.