Perhaps you should try some spelling variations:
nay thuc » nam thuc, cay thuc, day thuc
thuc dan » thuc hanh, hoc dan, thuc vat
dau tren » dau tien, dat tren, dau tieng
toc sac » toc sach, toc san, hoc sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
dan dan » dang dan, ban dan, dao dan
dan tai » van tai, dan thi, han tai
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
va nay » va ngay, va cay

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 nang xa hoi. hieu va nay thuc dan dan tai ((dau tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sac ky nang xa hoi. hieu va nay thuc dan dan tai ((dau tren) OR (cua tre)).
• Adding a wildcard symbol may retrieve word variants: toc sac ky nang xa hoi. hieu va nay thuc dan dan tai ((dau tren) or (cua tre))*.