Perhaps you should try some spelling variations:
thien van » thi van
hau truc » cau truc, hang truc, hoc truc
dang xay » dang van, van xay
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
va dinh » van dinh, va kinh, va tinh
va danh » va dan, va hanh, dia danh
van hau » van ha, van hai, van dau
nang xa » nang x, lang xa, nang ma
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: tu sach y ((nang xa) or (dang xay)) hoi. thien van hau truc ((va danh) OR (va dinh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (dang xay)) hoi. thien van hau truc ((va danh) OR (va dinh)) vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) or (dang xay)) hoi. thien van hau truc ((va danh) OR (va dinh)) vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (dang xay)) hoi. thien van hau truc ((va danh) OR (va dinh)) vai cua tre*.