Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
tay lang » tai lang, tay tang, tay quang
hanh vai » hanh vi, hanh va, hanh tai
vat hanh » vat thanh, van hanh, va hanh
su tien » su kien, su hien, tu tieng
tu sach » thu sach, su sach, te sach
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky dang » ky nang, ky danh
su viet » so viet

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 ((tay lang) or (ky dang)) hoa hoi. hieu van nam thuc vat hanh vai ((su tien) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tay lang) OR (ky dang)) hoa hoi. hieu van nam thuc vat hanh vai ((su tien) OR (su viet)).
• Adding a wildcard symbol may retrieve word variants: tu sach ((tay lang) or (ky dang)) hoa hoi. hieu van nam thuc vat hanh vai ((su tien) or (su viet))*.