Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
ty ngang » ly ngan, tu ngan, ty xang
khoa hoc » hoa hoc
cac luc » coc luc, cac nuoc, cac cuoc
van anh » van thanh, tuan anh, van minh
cau luc » cau truc, cau phuc
cua cau » cua cac, cua chu, cua cay
hieu ve » hieu va, hieu van
te ngan » tu ngan, tai ngan
anh vi » hanh vi, anh va, anh ve
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ty ngang) OR (te ngan)) khoa hoc. hieu ve ((cac luc) or (cau luc)) van anh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ty ngang) OR (te ngan)) khoa hoc. hieu ve ((cac luc) OR (cau luc)) van anh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((ty ngang) OR (te ngan)) khoa hoc. hieu ve ((cac luc) or (cau luc)) van anh vi cua cau*".