Perhaps you should try some spelling variations:
thong duong » tuong duong, thong dung, thong huong
canh trinh » canh tranh, hanh trinh, canh tinh
duong tan » duong tuan, duong van, duong tai
ho chieu » theo chieu, hoc thieu, doi chieu
trinh va » trinh van, trinh vat, trinh ve
va thong » va thuong, va phuong, he thong
doi chi » doi khi
tan van » tran van, tang van, luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chi) or (ho chieu)) tinh - canh trinh va thong duong tan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chi) OR (ho chieu)) tinh - canh trinh va thong duong tan van ban.
• Adding a wildcard symbol may retrieve word variants: ((doi chi) or (ho chieu)) tinh - canh trinh va thong duong tan van ban*.