Perhaps you should try some spelling variations:
dua tren » dung tren
thi hanh » thi thanh
quang xa » quan xa, quang ma, quang va
ly quang » le quang, vu quang
hieu va » lieu va, hieu qua
sach ly » sach y, sach lo, sach ty
cam tuc » cam xuc, cam tu, nam thuc
va dinh » van dinh, va kinh, va tinh
dinh vi » dinh ve, dinh viet, dinh tri
cuu tre » cua tre, cau tren, cau treo
tu sach » thu sach, su sach, te sach
tuc va » thuc va, truc va, tuc xa

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 ly quang xa hoi. ((hieu va) or (thi hanh)) cam tuc va dinh vi ((cuu tre) or (dua tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ly quang xa hoi. ((hieu va) OR (thi hanh)) cam tuc va dinh vi ((cuu tre) OR (dua tren)).
• Adding a wildcard symbol may retrieve word variants: tu sach ly quang xa hoi. ((hieu va) or (thi hanh)) cam tuc va dinh vi ((cuu tre) or (dua tren))*.