Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
hien sach » dien sach, kien sach, chieu sach
dung cong » dung trong
cong vang » cong lang, cong quang, cong ngang
vang tuan » van tuan, vong tuan, quang tuan
tuan bang » tuan dang, tuan hoang, thuat bang
tranh va » tranh van, trang va, trinh va
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien sach) or (thien hach)) - canh tranh va dung cong vang tuan bang~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sach) OR (thien hach)) - canh tranh va dung cong vang tuan bang.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) or (thien hach)) - canh tranh va dung cong vang tuan bang*.