Perhaps you should try some spelling variations:
hang dau » hang va, hang tai
ky hang » ky nang, ly hang, ky dang
dau hoi » cau hoi, dai hoi, dan hoi
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va hanh » van hanh, va thanh, va danh
luu tre » luu tru, cuu tre
luy tre » luyen tre
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky

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 hang dau hoi. hieu ve pham duc va hanh vi ((luu tre) or (luy tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky hang dau hoi. hieu ve pham duc va hanh vi ((luu tre) OR (luy tre)).
• Adding a wildcard symbol may retrieve word variants: te sac ky hang dau hoi. hieu ve pham duc va hanh vi ((luu tre) or (luy tre))*.