Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
van cham » van chat, van tham, va cham
cham tuc » nham thuc, pham thuc, tham thuc
hoc cac » hoc cao
nang xa » nang x, lang xa, nang ma
xa dinh » xac dinh, va dinh, ba dinh
ket cua » ket qua, det cua, keo cua
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (hoc cac)) ky nang xa hoi. thien van cham tuc xa dinh ket cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc cac)) ky nang xa hoi. thien van cham tuc xa dinh ket cua tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc cac)) ky nang xa hoi. thien van cham tuc xa dinh ket cua tre*.