Perhaps you should try some spelling variations:
cac nuoc » cap nuoc, dat nuoc, cua nuoc
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
vu sac » vu sach, vu san, va sac
sac ky » cac ky, sai ky
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sac ky ((nang xa) or (lang xa)) hoi. hieu ve ((cac nuoc) or (hoc nuoc)) va dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ky ((nang xa) OR (lang xa)) hoi. hieu ve ((cac nuoc) OR (hoc nuoc)) va dan vi cua tre.
• Adding a wildcard symbol may retrieve word variants: vu sac ky ((nang xa) or (lang xa)) hoi. hieu ve ((cac nuoc) or (hoc nuoc)) va dan vi cua tre*.