Perhaps you should try some spelling variations:
tranh qua » tranh cua, thanh qua, trinh qua
dung cong » dung trong
hoc hieu » hoc thieu, hoc hien, doc hieu
qua dung » quang dung, su dung, qua song
nhan vat » nhan va, nhan tai, nhan dan
hieu ca » hieu cac, hieu cua, hieu va
van vat » van chat
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: hoc hieu ca - canh tranh qua dung cong ((((van vat) OR (nhan vat))) or (tan van)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu ca - canh tranh qua dung cong ((((van vat) OR (nhan vat))) OR (tan van)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu ca - canh tranh qua dung cong ((((van vat) OR (nhan vat))) or (tan van)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu ca - canh tranh qua dung cong ((((van vat) OR (nhan vat))) or (tan van)) cau*.