Perhaps you should try some spelling variations:
hoc thieu » toc thieu, hoc hien
nang cong » nang song, dang cong, bang cong
cong vang » cong lang, cong quang, cong ngang
vang tuan » van tuan, vong tuan, quang tuan
ho chieu » theo chieu, doi chieu, mot chieu
trung va » truong va, trang va, trung ha
tran van » luan van
tuan cao » toan cao, juan cao, quang cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) OR (hoc thieu)) xanh - hanh ((trung va) or (tran van)) nang cong vang tuan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) xanh - hanh ((trung va) OR (tran van)) nang cong vang tuan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (hoc thieu)) xanh - hanh ((trung va) or (tran van)) nang cong vang tuan cao".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (hoc thieu)) xanh - hanh ((trung va) or (tran van)) nang cong vang tuan cao*.