Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach tru » sach truc, sach thu, sach tu
va kinh » va tinh, qua kinh
cao duc » dao duc, cao suc, giao duc
hieu va » lieu va, hieu qua
nang xa » lang xa, nang ma, mang xa
va cao » va cac, va co, va dao
va cua » va chua, via cua, ca cua
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: thu sach tru ((nang xa) OR (nang x)) hoi. hieu va cao duc ((va kinh) or (may tinh)) va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach tru ((nang xa) OR (nang x)) hoi. hieu va cao duc ((va kinh) OR (may tinh)) va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach tru ((nang xa) OR (nang x)) hoi. hieu va cao duc ((va kinh) or (may tinh)) va cua te".
• Adding a wildcard symbol may retrieve word variants: thu sach tru ((nang xa) OR (nang x)) hoi. hieu va cao duc ((va kinh) or (may tinh)) va cua te*.