Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hoc thieu » toc thieu, hoc hien
cong vang » cong quang, cong ngang, cong san
cong lang » cong luong, cong quang, cong ngang
chinh ca » chinh ta, chinh va, chinh tai
toan cao » toan ban, toan tap
hanh va » hang va, hanh vi

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 - hanh ((chinh ca) or (hanh va)) dung ((cong vang) or (cong lang)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - hanh ((chinh ca) OR (hanh va)) dung ((cong vang) OR (cong lang)) toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - hanh ((chinh ca) or (hanh va)) dung ((cong vang) or (cong lang)) toan cao*.