Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
vanh dai » van dai, vanh tai, lanh dao
hanh dai » hanh tai, hanh dao, thanh dat
thuc dan » thuc hanh, hoc dan, thuc vat
cua tre » cua te, cuu tre, cua triet
thuc va » thuc vat, thuc day
hieu ve » hieu va, hieu van
dang ha » dong ha, dung ha, lang ha
y dang » ky dang, 2 dang, _ dang
ve cau » ke cau, va cau, ve cac
ha hoi » hoa hoi, ha noi, xa hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach y dang ha hoi. hieu ve cau ((thuc va) or (thuc dan)) ((hanh dai) OR (vanh dai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach y dang ha hoi. hieu ve cau ((thuc va) OR (thuc dan)) ((hanh dai) OR (vanh dai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach y dang ha hoi. hieu ve cau ((thuc va) or (thuc dan)) ((hanh dai) OR (vanh dai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach y dang ha hoi. hieu ve cau ((thuc va) or (thuc dan)) ((hanh dai) OR (vanh dai)) cua tre*.