Perhaps you should try some spelling variations:
quyet thang » quyet thanh, quyet tranh, quyet toan
thang khoa » hang khoa, thong khoa, thanh hoa
thuoc sach » hoc sach, nuoc sach, thuat sach
khan thong » khap thong, khau thong, nhan thong
tao quyet » cao quyet, tao tuyet, ta quyet
sach tao » sach dao, sach bao, sach tham
sach tai » sach bai, sach tham, sach dao
thi benh » tai benh, tri benh, thi binh
benh kho » benh khong, benh phoi, benh hoc
kho khan » khoa kham, khoa than
tu sach » thu sach, su sach, te sach
khoa he » hoa he, khoa hoc, khong he
tai thi » tai chi

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 tao quyet thang khoa he thong ) or ( thuoc sach tai thi benh kho khan thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tao quyet thang khoa he thong ) OR ( thuoc sach tai thi benh kho khan thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tao quyet thang khoa he thong ) or ( thuoc sach tai thi benh kho khan thong ))*.