Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
thu sach » tu sach, thuat sach, thuoc sach
thanh do » thanh de, thanh pho, thanh hoa
xa thanh » va thanh, ha thanh, ta thanh
hoc sach » hoc sinh, hoc cac, hoc anh
cua viet » ca viet, hoa viet, cua vat
hieu ve » hieu va, hieu van
ve tham » va tham, ve cham, vi tham
thuc xa » thuc xay, tuc xa, thuc va
do cua » doi cua, co cua, de cua
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) or (hoc sach)) ky nang ((x hoi) or (xa hoi)). hieu ve tham thuc xa thanh do cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (hoc sach)) ky nang ((x hoi) OR (xa hoi)). hieu ve tham thuc xa thanh do cua viet.
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (hoc sach)) ky nang ((x hoi) or (xa hoi)). hieu ve tham thuc xa thanh do cua viet*.