Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
nam xuc » cam xuc, nam xua, nam thuc
lang xa » lang ha, dang xay, lang van
dang xa » dang xay, dang ha, dang va
cuu tre » cua tre, cau tren, cau treo
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach thien ((dang xa) or (lang xa)) hoi. hieu van nam xuc va thanh vi ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thien ((dang xa) OR (lang xa)) hoi. hieu van nam xuc va thanh vi ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su sach thien ((dang xa) or (lang xa)) hoi. hieu van nam xuc va thanh vi ((dua tren) or (cuu tre))*.