Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
vanh dai » van dai, vanh tai, lanh dao
van vanh » van anh, van hanh, van manh
thuc van » thuc vat, thuc dan, thuc va
qua cai » qua hai, qua cac, quan cau
va lang » va nang, hoa lang
va dang » van dang, va nang, da dang
qua ca » qua cac, qua cua, quan cau
cua te » cua tu

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 ((va dang) or (va lang)) xa hoi. hieu ((qua cai) or (qua ca)) thuc van vanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((va dang) OR (va lang)) xa hoi. hieu ((qua cai) OR (qua ca)) thuc van vanh dai cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach ((va dang) or (va lang)) xa hoi. hieu ((qua cai) or (qua ca)) thuc van vanh dai cua te*.