Perhaps you should try some spelling variations:
hanh thoi » hanh thuoc, nhanh thai, hanh noi
sach tham » sach nha
xanh khoa » anh khoa, doanh khoa, nganh khoa
hoa thong » hoa trong, hoa khong, hoa thon
sach bac » sach bai, sach dao, sach xa
bac thuc » bao thuc, bac thua, cach thuc
khoa hoa » khoa khoa, khoa hoc, khoa hoi
tu sach » thu sach, su sach, te sach
thoi he » khoi he, thoi hien, thoai hy
tham ve » tam ve, thanh ve
ve xanh » ve canh, ve hanh, ve thanh

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 bac thuc hanh thoi he thong ) or ( tu sach tham ve xanh khoa hoa thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach bac thuc hanh thoi he thong ) OR ( tu sach tham ve xanh khoa hoa thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach bac thuc hanh thoi he thong ) or ( tu sach tham ve xanh khoa hoa thong ))*.