Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hoc thieu » toc thieu, hoc hien
hang cong » dang cong, hang nong, bang cong
cong tang » cong thang, cong tan, cong lang
tang tan » tang van, tang tai, tang dan
va hang » van hang, va nang, va lang
tan cao » toan cao, tao cao, tay cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sach - ((thanh tung) or (thanh cong)) va hang cong tang tan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - ((thanh tung) OR (thanh cong)) va hang cong tang tan cao.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - ((thanh tung) or (thanh cong)) va hang cong tang tan cao*.