Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va triet » va thiet, va trien, ve triet
ban hanh » ban hang
nhan duc » nhan duoc, nhan luc, phan duc
su triet » su viet, su tien, ve triet
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
duc ban » duc tan, duc van, dua ban
nang xa » nang x, lang xa, mang xa
va nhan » van nhan, ca nhan, va phan

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