Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tri nang » thi nang, tra nang, tri bang
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
tu sach » su sach, te sach, tu cach
cuc ban » cua ban, cac ban, cuu ban
hoi cua » hoi chuc
van cau » van dau, van hau, van chat
cau cuc » cau cua, cau luc, cau truc
nang ma » tang ma, sang ma, nang cao
di cua » dai cua, doi cua, de cua

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) or (thu sach)) tri nang ma hoa. hieu van cau cuc ban hanh ((di cua) or (hoi cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) tri nang ma hoa. hieu van cau cuc ban hanh ((di cua) OR (hoi cua)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) tri nang ma hoa. hieu van cau cuc ban hanh ((di cua) or (hoi cua)) tre*.