Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, te sach
hieu ve » hieu van
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
y lang » o lang, tay lang, yen lang
_ lang » o lang, _ land
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((y lang) OR (_ lang)) xa hoi. ((hieu ve) or (hieu va)) cau truc va hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y lang) OR (_ lang)) xa hoi. ((hieu ve) OR (hieu va)) cau truc va hanh tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y lang) OR (_ lang)) xa hoi. ((hieu ve) or (hieu va)) cau truc va hanh tai cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y lang) OR (_ lang)) xa hoi. ((hieu ve) or (hieu va)) cau truc va hanh tai cua te*.