Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cau theo » cau thi, cau tao
tang xa » trang xa, tang ma, lang xa
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
thuc ca » thuc cua, thuc can, thuc cao
dan tai » van tai, dan thi, han tai
dan va » doan va, dan ca, ban va
va lam » van lam, va lap
va am » va cam

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 ky tang xa hoi. hieu ((va am) or (va lam)) thuc ca ((dan tai) or (dan va)) cau theo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky tang xa hoi. hieu ((va am) OR (va lam)) thuc ca ((dan tai) OR (dan va)) cau theo.
• Adding a wildcard symbol may retrieve word variants: toc sach ky tang xa hoi. hieu ((va am) or (va lam)) thuc ca ((dan tai) or (dan va)) cau theo*.