Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
hieu va » lieu va, hieu qua
va tuan » van tuan, va quan, va toan
va hanh » va thanh, va danh, ban hanh
luy tre » luyen tre
te sac » te sach, te cac
te san » te ban, ke san, tu san
vi luy » vi lua, vi luu

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) OR (te san)) ky lang xa hoi. hieu va tuan le ((va hanh) or (van hanh)) vi luy tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sac) OR (te san)) ky lang xa hoi. hieu va tuan le ((va hanh) OR (van hanh)) vi luy tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sac) OR (te san)) ky lang xa hoi. hieu va tuan le ((va hanh) or (van hanh)) vi luy tre".
• Adding a wildcard symbol may retrieve word variants: ((te sac) OR (te san)) ky lang xa hoi. hieu va tuan le ((va hanh) or (van hanh)) vi luy tre*.