Perhaps you should try some spelling variations:
cong thong » cong thuong, cong trong, dong thong
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
chieu ca » chieu cao, chieu day, nhieu cau
thong va » trong va, thong cua, truong va
va thang » van thang, va thanh, va thong
thang ca » thang cua, hang ca, tang ca
hieu ca » hieu cac, hieu cua, hieu va
tinh va » tich va, trinh van, trinh vat
va cong » tai cong, cua cong

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 ca) or (chieu ca)) - hanh tinh va cong thong va thang ca~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu ca) OR (chieu ca)) - hanh tinh va cong thong va thang ca.
• Adding a wildcard symbol may retrieve word variants: doc ((hieu ca) or (chieu ca)) - hanh tinh va cong thong va thang ca*.