Perhaps you should try some spelling variations:
tham duc » pham duc, than duc, thach duc
toc sach » hoc sach, doc sach, thuoc sach
hanh lai » hanh lam, hanh tai, thanh lap
hieu van » hieu va, thien van, lieu va
lai cua » dai cua, hai cua, lai chau
va hanh » van hanh, va thanh, va danh
tham du » thap du, tham do, pham duc
cao hoi » cau hoi, co hoi, cao hoc
ty nang » ky nang, ty xang, ty hang
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ty nang cao hoi. hieu van ((tham duc) or (tham du)) va hanh lai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty nang cao hoi. hieu van ((tham duc) OR (tham du)) va hanh lai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ty nang cao hoi. hieu van ((tham duc) or (tham du)) va hanh lai cua te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ty nang cao hoi. hieu van ((tham duc) or (tham du)) va hanh lai cua te*.