Perhaps you should try some spelling variations:
kham thuc » nham thuc, pham thuc, tham thuc
doc sach » hoc sach, toc sach, nuoc sach
su sach » so sach, vu sach
va danh » va dinh, va dan, va hanh
va tinh » may tinh
vu kham » vu khanh
hieu vu » hieu va, hieu ve, hieu su
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (doc sach)) ky lang xa hoi. hieu vu kham thuc ((va tinh) or (va danh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (doc sach)) ky lang xa hoi. hieu vu kham thuc ((va tinh) OR (va danh)) vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (doc sach)) ky lang xa hoi. hieu vu kham thuc ((va tinh) or (va danh)) vi cua tre*.