Perhaps you should try some spelling variations:
hanh doi » thanh doi, hanh noi, hang doi
sach ky » sach y, sach ty, sach kem
doi cuu » doi cua, doi cuoc
thuc va » thuc dan, thuc day
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va, hieu qua
xay hoi » xa hoi, tay hoi, cay phoi
sac ky » cac ky, sai ky
va lam » van lam, va lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) OR (sac ky)) van xay hoi. hieu va lam ((thuc va) or (thuc vat)) hanh doi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) van xay hoi. hieu va lam ((thuc va) OR (thuc vat)) hanh doi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) van xay hoi. hieu va lam ((thuc va) or (thuc vat)) hanh doi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sac ky)) van xay hoi. hieu va lam ((thuc va) or (thuc vat)) hanh doi cuu tre*.