Perhaps you should try some spelling variations:
nay thuc » nam thuc, cay thuc, day thuc
thuc day » thuc dan, thuc vat
cau tren » cu tren, dau tren, ca tren
toc sac » toc sach, toc san, hoc sach
ky lang » ky nang, ky dang, ky tang
lang ha » long ha
qua nay » qua ngay, qua xay, qua cay
day dan » day danh, dao dan, cay dan
dan vai » dan va, dan tai, dan vat
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
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: toc sac ky lang ha hoi. hieu qua nay thuc day dan vai ((cau tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sac ky lang ha hoi. hieu qua nay thuc day dan vai ((cau tren) OR (cua tre)).
• Adding a wildcard symbol may retrieve word variants: toc sac ky lang ha hoi. hieu qua nay thuc day dan vai ((cau tren) or (cua tre))*.