Perhaps you should try some spelling variations:
nhan thuc » nhan luc, dan thuc, toan thuc
chat thuc » thuat thuc, chat thai, chat huu
tang van » dang van, hoang van, trong van
cua tre » cua te, cuu tre, cua triet
vai cua » dai cua, hai cua, lai cua
don vai » don vi, don va, den vai
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
dan ky » van ky
va don » va dong, va doc, va do
tu dan » tuc dan, tu ban, cu dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu dan ky ((nang xa) or (tang van)) hoi. hieu va ((chat thuc) OR (nhan thuc)) va don vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu dan ky ((nang xa) OR (tang van)) hoi. hieu va ((chat thuc) OR (nhan thuc)) va don vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu dan ky ((nang xa) or (tang van)) hoi. hieu va ((chat thuc) OR (nhan thuc)) va don vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu dan ky ((nang xa) or (tang van)) hoi. hieu va ((chat thuc) OR (nhan thuc)) va don vai cua tre*.