Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sang mai » sang ma, sang tai, lang mai
cau tren » dau tren, ca tren, cau treo
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cu tren » tu tren, dua tren
y sang » _ sang, duy sang
ve dat » de dat, va dat, ve dao
nuoc » quoc, duoc, ngoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y sang mai hoi. hieu ve dat nuoc va danh vi ((cau tren) or (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y sang mai hoi. hieu ve dat nuoc va danh vi ((cau tren) OR (cu tren)).
• Adding a wildcard symbol may retrieve word variants: toc sach y sang mai hoi. hieu ve dat nuoc va danh vi ((cau tren) or (cu tren))*.