Perhaps you should try some spelling variations:
cua tre » cua te, cuu tre, cua triet
cac xuc » cam xuc, cac nuoc, chat xuc
hieu ve » hieu va, hieu van
tu ban » thu ban, te ban
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
vi cua » vai cua, di cua
tu san » thu san, tu can, vu san
ky va » ly va, ke va, my va
va xa » va xac, va xay, va xu
nuoc » quoc, duoc, ngoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu san) OR (tu ban)) ky va xa hoi. hieu ve ((cac xuc) or (hoc nuoc)) va dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu san) OR (tu ban)) ky va xa hoi. hieu ve ((cac xuc) OR (hoc nuoc)) va dan vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu san) OR (tu ban)) ky va xa hoi. hieu ve ((cac xuc) or (hoc nuoc)) va dan vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu san) OR (tu ban)) ky va xa hoi. hieu ve ((cac xuc) or (hoc nuoc)) va dan vi cua tre*.