Perhaps you should try some spelling variations:
bieu hien » dieu hien, dieu khien, bien phien
van hanh » van thanh, ban hanh, van anh
nang tai » hang tai, sang tai, nang cao
cap nuoc » dat nuoc
tang tai » hang tai, dung tai, sang tao
te sach » toc sach
sach ty » sach y, sach tu, sach thu
vi hoa » voi hoa, vi hoc, va hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty ((nang tai) OR (tang tai)) hoi. bieu hien ((cap nuoc) or (cam xuc)) van hanh vi hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((nang tai) OR (tang tai)) hoi. bieu hien ((cap nuoc) OR (cam xuc)) van hanh vi hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty ((nang tai) OR (tang tai)) hoi. bieu hien ((cap nuoc) or (cam xuc)) van hanh vi hoa viet".
• Adding a wildcard symbol may retrieve word variants: te sach ty ((nang tai) OR (tang tai)) hoi. bieu hien ((cap nuoc) or (cam xuc)) van hanh vi hoa viet*.