Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
sach ty » sach y, sach tu, xach tay
van cam » van nam, van lam, van cau
luc van » luoc van, luu van, duc van
cuu tre » cua tre, cau tren, cau treo
hang x » nang x, hoang xa, chang xu
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

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)) hang x hoi. hieu van cam ((luc van) or (duc tan)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) hang x hoi. hieu van cam ((luc van) OR (duc tan)) hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach thu)) hang x hoi. hieu van cam ((luc van) or (duc tan)) hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach thu)) hang x hoi. hieu van cam ((luc van) or (duc tan)) hanh vi cuu tre*.