Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
hanh dai » hanh tai, hanh dao, vanh dai
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sac ky) OR (sai ky)) nang xa hoi. hieu van cam thuc dan hanh dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sac ky) OR (sai ky)) nang xa hoi. hieu van cam thuc dan hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sac ky) OR (sai ky)) nang xa hoi. hieu van cam thuc dan hanh dai cua tre*.