Perhaps you should try some spelling variations:
gianh lai » gian lan
hieu van » hieu va, thien van, lieu va
va gianh » va gian, van giang, va giai
nam duoc » nam thuoc, da duoc, dat duoc
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
dai hoi » dai hoc, dai hai, dai moi
tai hoi » tai khoi, tai hai, tai hoe
ky sang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
te sac » te sach, te cac, te san

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky sang ((tai hoi) or (dai hoi)). hieu van ((nam duoc) or (cam xuc)) va gianh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky sang ((tai hoi) OR (dai hoi)). hieu van ((nam duoc) OR (cam xuc)) va gianh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: te sac ky sang ((tai hoi) or (dai hoi)). hieu van ((nam duoc) or (cam xuc)) va gianh lai cua tre*.