Perhaps you should try some spelling variations:
thien van » thi van
dang than » dang thanh, sang than, dang tran
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
van dat » van dao, van dau, dan dat
va dang » van dang, va nang, va lang
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu
x hoi » xa hoi, o hoi, x ho
nuoc » quoc, duoc, ngoc

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

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