Perhaps you should try some spelling variations:
thanh vi » hanh vi, thanh ve, nhanh vi
thanh va » thanh van, hanh va, thanh ha
thu sach » tu sach, thuat sach, thuoc sach
hieu ve » hieu va, hieu van
cac luu » cac luat, sach luu
luu van » cuu van, luan van, luu hanh
sach ky » sac ky, sach y, sach ty
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky tang xa hoi. hieu ve cac luu van ((thanh vi) or (thanh va)) ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky tang xa hoi. hieu ve cac luu van ((thanh vi) OR (thanh va)) ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: thu sach ky tang xa hoi. hieu ve cac luu van ((thanh vi) or (thanh va)) ((cua tre) or (cuu tre))*.