Perhaps you should try some spelling variations:
van doanh » toan doanh, van dong, van thanh
cham duc » pham duc, cham soc, pham duy
thu nang » thi nang, thu bang, tho nang
thu hang » thi hang, thuc hanh, thu huong
va doanh » vay doanh, va danh, hoa doanh
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
va cham » va chat, va tham
van cu » van cau, van chu, van cua
cu tre » cu tren, cua tre, cuu tre

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 ((thu nang) or (thu hang)) xa hoi. hieu va cham duc ((va doanh) or (van doanh)) van cu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((thu nang) OR (thu hang)) xa hoi. hieu va cham duc ((va doanh) OR (van doanh)) van cu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ((thu nang) or (thu hang)) xa hoi. hieu va cham duc ((va doanh) or (van doanh)) van cu tre*.