Perhaps you should try some spelling variations:
nang dong » nang song, lang dong, nang luong
toc sac » toc sach, toc san, hoc sach
cua tuc » cua duc, cua tu, cua thuoc
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
nang ho » nang hoc, nang co, tang ho
sac ky » cac ky, sai ky
cac tu » cac thu, cach tu, cac du
va do » va dao, va doc, va co
do vi » don vi, doc vi, do voi

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 ho) or (nang dong)) hoi. hieu va cac tu va do vi ((cua tuc) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sac ky ((nang ho) OR (nang dong)) hoi. hieu va cac tu va do vi ((cua tuc) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: toc sac ky ((nang ho) or (nang dong)) hoi. hieu va cac tu va do vi ((cua tuc) or (cuu tre))*.