Perhaps you should try some spelling variations:
hanh khoa » hang khoa, anh khoa, hanh hoa
hoc sach » hoc sinh, hoc cac
thi hanh » thi thanh
khoa hoc » hoa hoc
cac vuc » cac nuoc, cac vung, cac cuoc
hanh va » hang va, hanh vi
vuc van » duc van, luc van, thuc van
cua cau » cua cac, cua chu, cua cay
hieu ve » hieu va, hieu van
hoc anh » hoc nganh, hoc nhanh, ngoc anh
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: ((hoc sach) OR (hoc anh)) thi hanh khoa hoc. hieu ve cac vuc van ((anh va) or (hanh va)) cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (hoc anh)) thi hanh khoa hoc. hieu ve cac vuc van ((anh va) OR (hanh va)) cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc sach) OR (hoc anh)) thi hanh khoa hoc. hieu ve cac vuc van ((anh va) or (hanh va)) cua cau*".