Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
toc sach » hoc sach, doc sach, thuoc sach
lang van » dang van, tang van, hoang van
su sach » so sach, vu sach
va danh » va dinh, va dan, va hanh
va tinh » may tinh
hieu vu » hieu va, hieu ve, hieu su
vu pham » su pham, vi pham, vu kham
van hoi » van hoa, van hoc, van hoe
ky lang » ky nang, ky dang, ky tang
cuu tre » cua tre, cau tren, cau treo
vi cuu » vi luu, vinh cuu

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 (toc sach)) ky lang van hoi. hieu vu pham thuc ((va tinh) or (va danh)) vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky lang van hoi. hieu vu pham thuc ((va tinh) OR (va danh)) vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky lang van hoi. hieu vu pham thuc ((va tinh) or (va danh)) vi cuu tre*.