Perhaps you should try some spelling variations:
van tham » van thanh, van tuan, van chat
tham duc » pham duc, tham du, than duc
hieu van » hieu va, thien van, lieu va
hai chu » hai chau, hoi chu, hai chi
hai cuu » hai cua, hai cuc, thai cua
va danh » va dinh, va dan, va hanh
tu sach » thu sach, su sach, tu cach
cao hoi » cau hoi, co hoi, cao hoc
te sach » toc sach

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

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