Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cham duc » pham duc, cham soc, pham duy
su triet » su viet, su tien, ve triet
va cham » va chat, va tham
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, danh di
hang di » hang doi, hang vi, hang dien
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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 ((x hoi) or (o hoi)). lieu va cham duc van ((hanh di) OR (hang di)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((x hoi) OR (o hoi)). lieu va cham duc van ((hanh di) OR (hang di)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ((x hoi) or (o hoi)). lieu va cham duc van ((hanh di) OR (hang di)) su triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((x hoi) or (o hoi)). lieu va cham duc van ((hanh di) OR (hang di)) su triet*.