Perhaps you should try some spelling variations:
hoc chuyen » khong chuyen
kham xuong » khac xuong, kham xung, phan xuong
xuong doan » xuong dan, xuong hoan, phuong doan
sach tren » sach tien, sach tranh
thuc bach » thuc cach, thuoc sach, thuc hanh
khoa kham » kho khan, khoa than
doan tinh » doan hinh, ban tinh, quan tinh
tren hoc » truyen hoc, trung hoc, triet hoc
tu sach » thu sach, su sach, te sach

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 tren hoc chuyen đe ky thuat: kien ((thuc bach) OR (truc bach)) khoa kham xuong doan tinh~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tren hoc chuyen đe ky thuat: kien ((thuc bach) OR (truc bach)) khoa kham xuong doan tinh".
• Adding a wildcard symbol may retrieve word variants: tu sach tren hoc chuyen đe ky thuat: kien ((thuc bach) OR (truc bach)) khoa kham xuong doan tinh*.