Perhaps you should try some spelling variations:
thanh lai » thanh hai, thanh lap, thanh loi
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
thu sach » thuat sach, thuoc sach, thu hoach
van cau » van dau, van hau, van chat
tuc gia » tac gia, duc gia, toc gia
cau tuc » cau truc, cau tu, cau luc
tu sach » su sach, te sach, tu cach
nong va » nong van, dong va, cong va
tu nong » tu dong, tu cong, tu tong
cuu tre » cua tre, cau tren, cau treo
va hoi » xa hoi, va hoc, va hoa

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) or (thu sach)) tu nong va hoi. hieu van cau tuc gia thanh lai ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) tu nong va hoi. hieu van cau tuc gia thanh lai ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) tu nong va hoi. hieu van cau tuc gia thanh lai ((dua tren) or (cuu tre))*.