Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cach tu » cach thuc
va hanh » va thanh, va danh, ban hanh
cu tren » tu tren, dua tren
y lang » o lang, _ lang, tay lang
cac tu » cac thu, cac du, tac tu
vi cu » vi su, vi xu, vi du

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y lang xa hoi. hieu ve ((cac tu) or (cach tu)) ((va hanh) or (van hanh)) vi cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y lang xa hoi. hieu ve ((cac tu) OR (cach tu)) ((va hanh) OR (van hanh)) vi cu tren.
• Adding a wildcard symbol may retrieve word variants: tu sach y lang xa hoi. hieu ve ((cac tu) or (cach tu)) ((va hanh) or (van hanh)) vi cu tren*.