Perhaps you should try some spelling variations:
ngang khoa » nganh khoa, hang khoa, nganh hoa
doc sach » hoc sach, toc sach, nuoc sach
ty ngang » ly ngan, te ngan, tu ngan
khoa hoc » hoa hoc
cau luc » cau truc, cau phuc
cua cau » cua cac, cua chu, cua cay
sach ty » sach y, sach tu, sach thu
cac luc » coc luc, cac nuoc, cac cuoc
hieu ve » hieu va, hieu van
anh vi » hanh vi, anh va, anh vu
anh ve » hanh ve, anh va, anh viet

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

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