Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
te sach » toc sach
hieu va » lieu va, hieu qua
nam xuc » cam xuc, nam xua, nam thuc
dan vat » dang vat, van vat, dan va
cuu tre » cua tre, cau tren, cau treo
y dang » ky dang, 2 dang, b dang
_ dang » _ dan, 2 dang, _ danh
va nam » van nam, ha nam, va nay
xuc ca » xuc cam, xuc cua
ca dan » cac dan, ca dao

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 dang) OR (_ dang)) xa hoi. hieu va nam xuc ca dan vat ((cuu tre) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y dang) OR (_ dang)) xa hoi. hieu va nam xuc ca dan vat ((cuu tre) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y dang) OR (_ dang)) xa hoi. hieu va nam xuc ca dan vat ((cuu tre) or (dau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach ((y dang) OR (_ dang)) xa hoi. hieu va nam xuc ca dan vat ((cuu tre) or (dau tren))*.