Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
thai son » thai den, thai do, thai hoc
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va hanh » van hanh, va thanh, va danh
luu tre » cuu tre, luy tre
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
son va » song va, son la, lon va
tru » truc

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 lang xa hoi. ((hieu quan) or (hieu qua)) thai son va hanh vi ((luu tre) or (luu tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky lang xa hoi. ((hieu quan) OR (hieu qua)) thai son va hanh vi ((luu tre) OR (luu tru)).
• Adding a wildcard symbol may retrieve word variants: te sac ky lang xa hoi. ((hieu quan) or (hieu qua)) thai son va hanh vi ((luu tre) or (luu tru))*.