Perhaps you should try some spelling variations:
thuyet hoa » thuyet va, huyet hoc
bac thanh » ban thanh, cac thanh, tai thanh
sach than » sach tham, sach han, sach tranh
ky thuyet » ly thuyet, li thuyet, ly huyet
thuat co » thuat do, thuat o
thanh ky » hanh ky, thanh tay, thanh huy
te sach » toc sach
te bac » ten bac, te bao, te ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach than ky thuat co hoc ) or ( te bac thanh ky thuyet hoa hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach than ky thuat co hoc ) OR ( te bac thanh ky thuyet hoa hoc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach than ky thuat co hoc ) or ( te bac thanh ky thuyet hoa hoc ))*.