Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tham thuc » nham thuc, pham thuc, tam thuc
cham tuc » nham thuc, pham thuc, cham soc
hanh doi » thanh doi, hanh noi, hang doi
hieu van » hieu va, thien van, lieu va
doi cua » dai cua, hoi cua, dong cua
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
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: ((tu sach) or (thuat sach)) ky nang x hoi. hieu van ((cham tuc) OR (tham thuc)) va hanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuat sach)) ky nang x hoi. hieu van ((cham tuc) OR (tham thuc)) va hanh doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuat sach)) ky nang x hoi. hieu van ((cham tuc) OR (tham thuc)) va hanh doi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuat sach)) ky nang x hoi. hieu van ((cham tuc) OR (tham thuc)) va hanh doi cua tre*.