Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
tu cach » tu cac
vat dan » va dan, van dan, vat ran
hieu ve » hieu va, hieu van
van hoi » van hoa, van hoc, van hoe
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
ve nam » he nam, va nam, le nam
dan va » doan va, dan ca, ban va
va cua » va chua, via cua, ca cua
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: ((tu cach) or (thu sach)) ((ky lang) or (ky tang)) van hoi. hieu ve nam thuc vat dan va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) ((ky lang) OR (ky tang)) van hoi. hieu ve nam thuc vat dan va cua te.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thu sach)) ((ky lang) or (ky tang)) van hoi. hieu ve nam thuc vat dan va cua te*.