Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
dau tren » dau tien, dat tren, dau tieng
may hoi » may thoi, tay hoi, mai hoi
hieu va » lieu va, hieu qua
xuc van » vuc van, xuc ban, thuc van
luc van » luoc van, luu van, luc va
duc van » duc va, duc tan, duc manh
y mang » cay mang
anh vi » hanh vi, anh va, anh ve
vi dau » vi dai, va dau, bi dau

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 mang may hoi. hieu va cac ((xuc van) or (((luc van) OR (duc van)))) anh vi dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y mang may hoi. hieu va cac ((xuc van) OR (((luc van) OR (duc van)))) anh vi dau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y mang may hoi. hieu va cac ((xuc van) or (((luc van) OR (duc van)))) anh vi dau tren*".