Perhaps you should try some spelling variations:
hieu quan » hieu qua, lieu quan, thien quan
than luc » nhan luc, than duc, thanh luu
hoa lang » hoa dan, hoa van
su sach » so sach, vu sach
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
van hoi » van hoa, van hoc, van hoe
ha luc » ha duc, nhan luc
o lang » hoi lang
di cua » dai cua, doi cua, de cua
cua te » cua tu

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 ((o lang) or (hoa lang)) van hoi. hieu quan ((ha luc) OR (than luc)) va hanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((o lang) OR (hoa lang)) van hoi. hieu quan ((ha luc) OR (than luc)) va hanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((o lang) or (hoa lang)) van hoi. hieu quan ((ha luc) OR (than luc)) va hanh di cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((o lang) or (hoa lang)) van hoi. hieu quan ((ha luc) OR (than luc)) va hanh di cua te*.