Perhaps you should try some spelling variations:
thuat tac » thuat tach, thuat tao, thuat tai
nam truoc » nam thuoc, lam truoc, nam truc
thai viet » thi viet, tai viet, mai viet
truoc va » truc va, thuoc va, truong va
hanh voi » hanh vi, hanh noi, hanh moi
hai viet » mai viet, tai viet, dai viet
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
tac ky » tac ke, cac ky, tap ky
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat tac ky lang xa hoi. hieu va nam truoc va hanh voi ((thai viet) or (hai viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat tac ky lang xa hoi. hieu va nam truoc va hanh voi ((thai viet) OR (hai viet)).
• Adding a wildcard symbol may retrieve word variants: thuat tac ky lang xa hoi. hieu va nam truoc va hanh voi ((thai viet) or (hai viet))*.