Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
nang tai » hang tai, tang tai, sang tai
van hanh » van thanh, ban hanh, van anh
cua viet » ca viet, hoa viet, cua vat
sach ty » sach y, sach tu, sach thu
nang ma » tang ma, sang ma, nang cao
cac xuc » cac nuoc, chat xuc, cac cuoc
hanh di » hanh vi, hanh de, hang di
su sach » so sach, vu sach
di cua » dai cua, doi cua, de 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 ty ((nang ma) or (nang tai)) hoi. hieu hien ((cac xuc) or (cam xuc)) van hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang ma) OR (nang tai)) hoi. hieu hien ((cac xuc) OR (cam xuc)) van hanh di cua viet.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang ma) or (nang tai)) hoi. hieu hien ((cac xuc) or (cam xuc)) van hanh di cua viet*.