Perhaps you should try some spelling variations:
thanh lai » thanh hai, thanh lap, thanh loi
van thanh » ban thanh, van tuan
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
than duc » tran duc, phan duc, than doc
tham luc » than luc, tham nuoc, tham thuc
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
lai cua » dai cua, hai cua, lai chau
tu sach » thu sach, su sach, te sach

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 ((ky lang) OR (ky dang)) xa hoi. hieu van ((tham luc) or (than duc)) van thanh lai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu van ((tham luc) OR (than duc)) van thanh lai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) OR (ky dang)) xa hoi. hieu van ((tham luc) or (than duc)) van thanh lai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu van ((tham luc) or (than duc)) van thanh lai cua viet*.