Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hanh tai » thanh tai, hang tai, han tai
hieu va » lieu va, hieu qua
cuc tre » cua tre, cuu tre, cuc thue
va hanh » van hanh, va thanh, va danh
duoc va » nuoc va, duc va, duoc ma
tu cach » tu cac
lang ha » long ha
ky lang » ky nang, ky dang, ky tang
duc tre » duoc tren, duc tien
ha hoi » hoa hoi, ha noi, xa hoi
va tao » va bao, va cao, va tac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (thuat sach)) ky lang ha hoi. hieu va tao duoc va hanh tai ((cuc tre) OR (duc tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thuat sach)) ky lang ha hoi. hieu va tao duoc va hanh tai ((cuc tre) OR (duc tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thuat sach)) ky lang ha hoi. hieu va tao duoc va hanh tai ((cuc tre) OR (duc tre))".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thuat sach)) ky lang ha hoi. hieu va tao duoc va hanh tai ((cuc tre) OR (duc tre))*.