Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cham thuc » nham thuc, pham thuc, tham thuc
su triet » su viet, su tien, ve triet
dan hanh » dang hanh, dan khanh, dan thanh
thuc dan » thuc hanh, hoc dan, thuc vat
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
te sach » toc sach
hanh ki » hanh vi, hanh ky, hanh kien
tu sach » thu sach, su sach, tu cach
ki su » ky su

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 (te sach))) or (thuoc sach)) ky lang xa hoi. hieu ve cham thuc dan hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((tu sach) OR (te sach))) OR (thuoc sach)) ky lang xa hoi. hieu ve cham thuc dan hanh ki su triet.
• Adding a wildcard symbol may retrieve word variants: ((((tu sach) or (te sach))) or (thuoc sach)) ky lang xa hoi. hieu ve cham thuc dan hanh ki su triet*.