Perhaps you should try some spelling variations:
hieu quan » thien quan, lien quan, hieu luat
lieu quan » lien quan, lieu van
luu tre » luu tru, cuu tre, luy tre
ky lang » ky nang, ky dang, ky tang
lang ha » long ha
va hanh » van hanh, va thanh, va danh
thai do » thay doi, thai den
vi luu » vi lua
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
ha hoi » hoa hoi, ha noi, xa hoi
do va » do van, so va

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 ha hoi. ((((hieu quan) OR (lieu quan))) or (hieu qua)) thai do va hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky lang ha hoi. ((((hieu quan) OR (lieu quan))) OR (hieu qua)) thai do va hanh vi luu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky lang ha hoi. ((((hieu quan) OR (lieu quan))) or (hieu qua)) thai do va hanh vi luu tre*".