Perhaps you should try some spelling variations:
hanh trinh » canh tranh
thiet bang » thien bang, khien bang, nhiet nang
hien sach » dien sach, kien sach, thien hach
bang cong » dang cong, bang song, hang cong
cong van » cong vang, cong san, song van
hang cac » hang cau, bang cac, hanh cac
hang ca » hang va, nang cao, hang tai

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 - ((hanh trinh) or (hanh chinh)) thiet bang cong van ((hang cac) OR (hang ca))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien sach - ((hanh trinh) OR (hanh chinh)) thiet bang cong van ((hang cac) OR (hang ca)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien sach - ((hanh trinh) or (hanh chinh)) thiet bang cong van ((hang cac) OR (hang ca))".
• Adding a wildcard symbol may retrieve word variants: hoc hien sach - ((hanh trinh) or (hanh chinh)) thiet bang cong van ((hang cac) OR (hang ca))*.