Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
hieu cach » hieu cac, chieu sach, hieu ca
hanh hang » thanh hang, hang hang, hanh han
doc hieu » toc thieu, hoc thieu, hoc hien
thi hang » thi hanh, thi hong, thi thanh
thi nang » thi cong, ki nang, thi hanh
san cau » van cau, ban cau, can cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu cach - hanh hang ((thi hang) or (thi nang)) cong thanh san cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu cach - hanh hang ((thi hang) OR (thi nang)) cong thanh san cau.
• Adding a wildcard symbol may retrieve word variants: doc hieu cach - hanh hang ((thi hang) or (thi nang)) cong thanh san cau*.