Perhaps you should try some spelling variations:
thanh lap » thanh san, phan lap, thanh hai
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
duc manh » suc manh, duc minh, duc tan
sach ty » sach y, sach tu, xach tay
lang xa » lang ha, dang xay, lang van
lap cua » lai cua, tap cua, lam cua
cua tre » cua te, cuu tre, cua triet

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 ty) or (sach thu)) lang xa hoi. hieu van nam ((duc manh) or (duc anh)) thanh lap cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) lang xa hoi. hieu van nam ((duc manh) OR (duc anh)) thanh lap cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) lang xa hoi. hieu van nam ((duc manh) or (duc anh)) thanh lap cua tre*.