Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
phat duc » pham duc, phan duc, phan duoc
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, lieu va, hieu ve
tai cua » thai cua, tai cuc, tri cua
duc van » duc va, duc tan, duc manh
van hoe » van hoa, van hoc, van hieu
ky lang » ky dang, ky tang, tay lang
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ky lang) or (ky nang)) van hoe. ((hieu van) or (thien van)) phat duc van hanh tai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky lang) OR (ky nang)) van hoe. ((hieu van) OR (thien van)) phat duc van hanh tai cua tu.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky lang) or (ky nang)) van hoe. ((hieu van) or (thien van)) phat duc van hanh tai cua tu*.