Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh vi » thanh va, thanh ve, nhanh vi
cau tren » dau tren, ca tren, cau treo
hieu va » lieu va, hieu qua
cau luc » cau truc, cau phuc
xang xa » lang xa, mang xa, ang xa
cu tren » tu tren, dua tren
va cau » van cau, va cac, va dau
luc va » duc va, tuc va, loc va
y xang » ty xang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach y xang xa hoi. hieu va cau luc va ((thanh vi) or (hanh vi)) ((cau tren) OR (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y xang xa hoi. hieu va cau luc va ((thanh vi) OR (hanh vi)) ((cau tren) OR (cu tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y xang xa hoi. hieu va cau luc va ((thanh vi) or (hanh vi)) ((cau tren) OR (cu tren))".
• Adding a wildcard symbol may retrieve word variants: thuoc sach y xang xa hoi. hieu va cau luc va ((thanh vi) or (hanh vi)) ((cau tren) OR (cu tren))*.