Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
day hanh » day nhanh, day thanh, dao hanh
cac nhan » ca nhan, cac nha, cam nhan
dac nhan » danh nhan, ca nhan, cac nha
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
te cua » tue cua, le cua, de cua
x hoi » xa hoi, o hoi, x ho

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 ty nang x hoi. hieu ve cham thuc ((day hanh) or (((dac nhan) OR (cac nhan)))) te cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang x hoi. hieu ve cham thuc ((day hanh) OR (((dac nhan) OR (cac nhan)))) te cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang x hoi. hieu ve cham thuc ((day hanh) or (((dac nhan) OR (cac nhan)))) te cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x hoi. hieu ve cham thuc ((day hanh) or (((dac nhan) OR (cac nhan)))) te cua tre*.