Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
van nhan » van phan, van thanh, danh nhan
ban hanh » ban hang
su triet » su viet, su tien, ve triet
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va nhan » ca nhan, va phan, va nha
luc ban » duc ban, cuc ban, luc bat

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 lang xa hoi. hieu ((va nhan) OR (van nhan)) luc ban hanh vi ((va thiet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky lang xa hoi. hieu ((va nhan) OR (van nhan)) luc ban hanh vi ((va thiet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky lang xa hoi. hieu ((va nhan) OR (van nhan)) luc ban hanh vi ((va thiet) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky lang xa hoi. hieu ((va nhan) OR (van nhan)) luc ban hanh vi ((va thiet) or (su triet))*.