Perhaps you should try some spelling variations:
khoa viet » khoan viet, hoa viet, thoai viet
truoc va » truc va, thuoc va, truong va
hanh voi » hanh vi, hanh noi, hanh moi
voi khoa » noi khoa, hoi khoa, loi khoa
lang xa » lang ha, dang xay, lang van
va hanh » van hanh, va thanh, va danh
sac ky » sai ky
va nay » va ngay, va cay
va nam » van nam, ha nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((sac ky) or (cac ky)) lang xa hoi. hieu ((va nam) OR (va nay)) truoc va hanh voi khoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sac ky) OR (cac ky)) lang xa hoi. hieu ((va nam) OR (va nay)) truoc va hanh voi khoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sac ky) or (cac ky)) lang xa hoi. hieu ((va nam) OR (va nay)) truoc va hanh voi khoa viet".
• Adding a wildcard symbol may retrieve word variants: thuat ((sac ky) or (cac ky)) lang xa hoi. hieu ((va nam) OR (va nay)) truoc va hanh voi khoa viet*.