Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
van nhan » van phan, van thanh, danh nhan
va triet » va thiet, va trien, ve triet
su triet » su viet, su tien, ve triet
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
luc ban » cuc ban, luc bat, luc van
duc ban » duc tan, duc van, dua ban

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 ty nang x ho. hieu van nhan ((luc ban) or (duc ban)) hanh vi ((va triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ty nang x ho. hieu van nhan ((luc ban) OR (duc ban)) hanh vi ((va triet) OR (su triet)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach ty nang x ho. hieu van nhan ((luc ban) or (duc ban)) hanh vi ((va triet) or (su triet))*.