Perhaps you should try some spelling variations:
thieu nien » thien nhien
nien sach » dien sach, kien sach, nen sach
sach nuoc » sach duoc, cac nuoc, bach tuoc
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky ((nang xa) or (nang x)) hoi. thieu nien sach nuoc va hanh di ((cua te) OR (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang xa) OR (nang x)) hoi. thieu nien sach nuoc va hanh di ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky ((nang xa) or (nang x)) hoi. thieu nien sach nuoc va hanh di ((cua te) OR (cua tu))".
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang xa) or (nang x)) hoi. thieu nien sach nuoc va hanh di ((cua te) OR (cua tu))*.