Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
ve triet » va trien, su triet
su sach » so sach, vu sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
can ban » van ban, toan ban
co duc » co duoc, cao duc, do duc
va can » va chan, va cac, va cao
ban ve » ban va
va co » vo co

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 thu ((nang xa) or (lang xa)) hoi. hieu va co duc va can ban ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu ((nang xa) OR (lang xa)) hoi. hieu va co duc va can ban ve triet.
• Adding a wildcard symbol may retrieve word variants: su sach thu ((nang xa) or (lang xa)) hoi. hieu va co duc va can ban ve triet*.