Perhaps you should try some spelling variations:
dua tren » dung tren
cuu tre » cua tre, cau tren, cau treo
va hanh » van hanh, va thanh, va danh
cam luc » cam xuc, cau luc
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
tang xa » trang xa, lang xa, tang ha
tang ma » mang may, tang van
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
luc va » duc va, tuc va, loc va

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 ty ((tang xa) OR (tang ma)) hoi. hieu va cam luc va hanh vi ((cuu tre) or (dua tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((tang xa) OR (tang ma)) hoi. hieu va cam luc va hanh vi ((cuu tre) OR (dua tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((tang xa) OR (tang ma)) hoi. hieu va cam luc va hanh vi ((cuu tre) or (dua tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((tang xa) OR (tang ma)) hoi. hieu va cam luc va hanh vi ((cuu tre) or (dua tren))*.