Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
xa hanh » xa thanh, xa khanh, va hanh
hanh ve » hanh vi, hanh va, hanh kem
cu tren » tu tren, dua tren
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, x ho

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 tu nang x hoi. hieu va cam tuc xa hanh ve ((cau thi) or (((cu tren) or (dau tren))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu nang x hoi. hieu va cam tuc xa hanh ve ((cau thi) OR (((cu tren) OR (dau tren)))).
• Adding a wildcard symbol may retrieve word variants: te sach tu nang x hoi. hieu va cam tuc xa hanh ve ((cau thi) or (((cu tren) or (dau tren))))*.