Perhaps you should try some spelling variations:
thien van » thi van
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
te sach » toc sach
van bac » van ban, van bao, van hac
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, hang di
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
x hoi » o 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: te sach y nang ((x hoi) OR (xa hoi)). thien van bac duc van hanh di ((su triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((x hoi) OR (xa hoi)). thien van bac duc van hanh di ((su triet) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ((x hoi) OR (xa hoi)). thien van bac duc van hanh di ((su triet) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((x hoi) OR (xa hoi)). thien van bac duc van hanh di ((su triet) or (cuu tre))*.