Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
cua viet » ca viet, hoa viet, cua vat
mai khoi » mai khoa, tai khoa, cac khoi
nang mai » nang ma, nang tai, lang mai
cac xuc » cac nuoc, chat xuc, cac cuoc
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach thu) or (sach y)) nang mai khoi. hieu hien ((cac xuc) or (cam xuc)) van hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach thu) OR (sach y)) nang mai khoi. hieu hien ((cac xuc) OR (cam xuc)) van hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: su ((sach thu) or (sach y)) nang mai khoi. hieu hien ((cac xuc) or (cam xuc)) van hanh vi cua viet*.