Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thu sach » tu sach, thuat sach, thu hoach
sang mai » sang ma, sang tai, lang mai
van lam » van nam
danh du » danh dau, danh tu, dinh du
va danh » va dinh, va dan, va hanh
cu tren » tu tren, dua tren
mai hoi » mai khoi, dai hoi, lai hoi
loc va » hoc va, luc va
y sang » _ sang, duy sang
va lam » va lap
du cu » cu cu, su cu, da cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) or (thuoc sach)) y sang mai hoi. hieu ((va lam) OR (van lam)) loc va danh du cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuoc sach)) y sang mai hoi. hieu ((va lam) OR (van lam)) loc va danh du cu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thuoc sach)) y sang mai hoi. hieu ((va lam) OR (van lam)) loc va danh du cu tren".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thuoc sach)) y sang mai hoi. hieu ((va lam) OR (van lam)) loc va danh du cu tren*.